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FAQs about Marine Snail Disease/Health

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Related FAQs: Marine Snails 1Marine Snails 2Marine Snails 3, Snail ID 1, Snail ID 2, Snail Behavior, Snail Selection, Snail Compatibility, Snail Systems, Snail Feeding, Snail Reproduction, MollusksSea SlugsAbalone

Sudden snail die off, some, not all...      3/18/13
Hi WetWebMedia crew, I'm a long time reader, first time caller! I came home from work this morning and noticed three banded Trochus, one turban, and one Nassarius snail all lying belly up in the sand.
<Mmm, summat off here. Ca/Mg ratio?>
Their feet looked healthy but were otherwise listless. None grabbed onto the rocks when placed right side up. All have been in the tank for about two months and have been previously very active and healthy. A money cowry, three Nerites, and a second turban snail look healthy,
<Hmm>
as do my tuxedo urchin, red Fromia starfish, two crocea clams and a maxima clam. Their are two small wrasses
<What species are these Labrids>
 and an ocellaris clown that are quite happy as well. The tank is a Red Sea Max 130D with all factory equipment plus an additional circulation pump. My parameters as of this morning are: s.g. 1.025, pH 8.3, dKH 12, Nitrite 0 ppm, and Nitrate 10-20 ppm (it's always this level despite weekly water changes, additional circulation, ChemiPure elite carbon, and SeaChem Denitrate). I checked the copper level in case something contaminated the water and it is zero.
<All invertebrates would be mal-affected...>
My maintenance schedule has been unchanged except for a scheduled carbon and Denitrate change last week. My star polyps began a massive spawn two days ago and I am wondering if the little pink packets are toxic to the snails.
<Could well be>
The fish won't touch them so I assume there is something that makes them unpalatable. I did a 20% water change and siphoned out as many of the packets that I could capture. Could the packets that got sucked into the overflow be decomposing and releasing toxins back into the tank?
<Yes>
 Thanks for maintaining such an informative website. Regards, Doug
<When, where in doubt... successive partial water changes. Bob Fenner>
Re: Sudden snail die off     3/18/13

Mr. Fenner, Thanks for the quick reply. I am thinking more that the problem is the spawning star polyps. All but one of the snails seem to be back to their prior health after yesterday's water change. They are moving around the rocks and adhering well. The final snail looks a tad better but still weak compared to the others. I am going to do another 20 % water change today and keep an eye on them. Thanks again, Doug.    
<Welcome>
P.S. the wrasses are a small radiant wrasse and a small yellow wrasse
<Ahh, these/Halichoeres should be okay>
. Neither pay much attention to the snails and did not bother them even when they we belly up. The Denitrate is Seachem de*nitrate media.
<Ah, yes>
My maintenance schedule is weekly water changes, carbon and Denitrate changes every 2 months (sooner if nitrates start increasing), daily buffer with Seachem marine buffer (1 teaspoon mixed in top off water) and every other day Brightwell Calcion (1/2 capful). The tank has been running two years and other than the nitrate is very stable.
<Thank you for this further input; and good news. Cheers, BobF>

High Magnesium and Turbo Snails    2/4/13
Hello crew, hope you are well. I've written several times before about my inability to keep Turbo Snails alive in my hair-algae-infested 29 gallon FOWLR tank. I'm still having the problem. My magnesium reads at 1500 ppm or slightly above with my Salifert kit. I've seen statements that magnesium is a muscle relaxant for snails.
<Yes... for most all animals>
 They die within a week or so, and do seem to fall down a lot before they succumb. I've tried Instant Ocean and Tropic Marin salts lately, and the newly-mixed saltwater always tests at 1500 or above.
<Strange. You want it, [Mg], to be about three times the concentration of Calcium>
I went to a good fish store today, and they confirmed the 1500 magnesium reading. They said this was surprising, since salt mixes generally produces less magnesium than this (especially Instant Ocean).
<Agreed>
They suggested the extra magnesium may be coming from my water source (RO, but not DI).
<Mmm, nah>
I tried to test for magnesium in my RO water, but the Salifert Mg test kit doesn't seem to work with fresh water. So my questions: is this magnesium level (with a calcium level generally between 400 and 450) capable of killing turbo snails in a couple of weeks?
<Yes; it can>
(Other inverts, such as Margarita Snails and Fire Shrimp, seem to do OK in the tank.) Is it likely for 100 to 200 ppm of magnesium to pass through my RO filter?
<Not>
 Is there a way I can test for it (i.e. a test that works in fresh water)?
<There are... you might look on Hach and LaMotte's websites... or a lab nearby or distal that you can send a sample to for testing>
I don't want to buy a DI filter without a good reason. Thanks, Jerry
<Welcome. Please do report back to us w/ your further findings. Bob Fenner>

Parasite snails    8/15/12
I have some small snails hanging out on my turbo snails, I'm positive they are a parasite of some sort.
<Yep, Pyramidellids.>
I only have two Turbos, both of them have 5-6 of these little snails hanging out on them at all times.
<Likely many more. They retreat into the sandbed after they have had there fill. The Pyramids are also feeding on your Collonistas, Limpets, and other gastropod hitch-hikers.>>
 I've had the Turbos themselves about 6 months, they have been surviving just fine with the parasites. My concern is if they will eventually kill the turbo?
<Pyramid snails reproduce rapidly; the damage inflicted will rise as the population increases.>
 It doesn't seem to be what would happen based off how well they are doing over the last half year, but I suppose it could happen.
<It can.>
 My other concern is I eventually want to have a T. squamosa or deresa, and I've heard about little parasite snails on clams being a huge nuisance and eventually fatal to the clam. If these snails can parasitize (that a word?)
more than one species, then I'm worried.
<There are thousands of species of Pyramidellids. Some attack other snails, some only eat clams, and some are not so picky moving from one to the other.>
 But if they are obligate turbo snail parasites, then I'm not so concerned.
<I would manually remove them as I see them. There are quite a few wrasse that will eat them. Thalamita sima will prey on Pyramids but finding a properly identified one for sale may prove difficult.
Thanks for all the help! You guys are great.
<Quite welcome.>
Grant
<Jordan>

Tiger Cowry, and [Mg]  2/27/12
I am currently fighting off a Bryopsis infestation using elevated magnesium (Tech M).
<Mmm>
 My Tiger Cowry, usually very mobile each evening, has not moved in two nights.  He shows little signs of distress other than the lack of relocation, but I am curious if you know of any sensitivity to elevated magnesium. 
<Oh yes... all Mollusks, not just Cypraeids. Not just too high or low concentrations, but too far out of ratio w/ [Ca].>
Current level is approximately 1680 ppm.
Thanks,
JD
<Welcome. Bob Fenner>
Re: Tiger Cowry  2/27/12
Thank you.  Very much appreciated.  I'll research proper ratios for future reference,
<Please read here re: http://www.wetwebmedia.com/mgmarart.htm
and the Related FAQs file linked above>
but I believe I'll relo him to my mini-tank for the duration of the treatment.
<Ah yes... I would definitely do so. BobF>
JD

Reef Crystals, re snail die-off...  6/24/10
<Hello Tom>
Hey all, just a quick question,
I have tried researching this and have read several threads on Reef Crystals but most are older. I have a 300g system, heavy sps, 6 months old, has RDSB, tons of live rock, fish etc. . I have many years experience keeping
sps and in reefing but I have never seen mass die offs of Trochus snails (red banded). These are the big fat guys, Petco sells them. They are great snails because they usually can flip them selves over. I bought 25 a few weeks in two different lots, acclimated them etc, I'm now down to 2 and can't figure out why. All my param.s are in check, o trate, 9 dKH Alk, 460 ca, 0 ammonia, 0 trite etc. . All my sps and corals are doing great so I'm not getting why the massive snail die off. I'm seriously thinking of switching to Tropic Marin.
<Do you have predators in your tank that would relish snails? Another thought is that they may be starving to death. Fifty Trochus Snails is a bit much for a 300 gallon tank, and, since their main diet is algae, there likely isn't enough food to satisfy all. Although Tropic Marin is an excellent product and use it myself, switching to it will do nothing to
cure your snail die off. I'd hold off adding any more snails and see how the survivors will fair.>
Have you guys had any reports of issues with small inverts and Reef Crystals lately? I have shrimp and they are happy as all get out, puzzled.
<Have heard nothing in that regard.>
Thanks,
<You're welcome. James (Salty Dog)>
Tom

Lethargic Snails: Possible Lack of Food - 5/13/10
Hey crew,
<Hello there Sam, Lynn here today.>
I have recently noticed that my Turbo snails have become lethargic (One clings to a rock, moving an inch at most a day, while the other has been retracted into its shell, motionless).
<Hmmm, that's not good. You might want to give the retracted, motionless snail the "sniff test" to make sure it's not already dead. Trust me, if it is, one sniff will prove it. If you have tongs or gloves, this would be a good time to use them. The last thing you want on your hands is dead snail juice - yikes! By the way, how long have you had these snails? Do you know what species they are? Are they the only snails you have? If not, how are the others doing?>
My clownfish is still feeding, however spends most of its time swimming into the glass in the bottom corner next to the 15-gallon rated heating fixture.
<As long as the fish is still feeding and you don't see any other outward signs of disease (white spots, etc.) then I wouldn't worry too much. Clowns can exhibit some pretty strange behavior at times but be perfectly healthy. I'd just keep an eye on it.>
My tank is a 14 gallon bio-cube, 78 degrees,
<That's on the low end, but okay.>
..with all parameters acceptable (zero nitrites, nitrates, ammonia, etc.). I have not yet measured important trace elements such as magnesium and phosphorous
<Phosphates? I take it that you're not adding anything (like magnesium) without testing first, right? Too much magnesium can have a negative effect on snails in that it works as a muscle relaxant. The main symptom is usually the inability to hang onto the glass. If you're adding it, definitely stop until you get the test kit. It would also be a good idea to perform a water change.>
..as my order for those test kits is going real slow.
<It happens>
In the meanwhile, do you have any ideas as to what may be afflicting my tank?
<Hmmm, well several things come to mind (if it's not the magnesium issue). First of all, the snails may well be starving. Turbos have huge appetites and two in a 14g is too much unless you really have a runaway algae problem. Honestly, I wouldn't recommend one in a tank that size, much less two. Fortunately, they'll accept dried seaweed sheets (Nori) that you can get either at the grocery store (the same sheets used for sushi), or at a local fish store. I would rubber band some to a rock and place it near the Turbo that's still clinging. I'd also pick up the other (confirmed alive) snail and place it on, or next to, the seaweed covered rock and see what happens. Hopefully they'll both respond and begin feeding. Beyond the possibility of starvation, sometimes Turbos 'home' in on one spot and stay there during the day after spending the night grazing algae off the glass. It can appear that they're inactive when actually they're just 'hanging out' waiting for darkness to fall. What's troublesome though is the combination of an inactive (but thankfully still clinging) snail and one that's just lying there. That's not good.>
I have checked the archives and haven't seen anything about "lethargic snails" and do not expect them to be old, as they are under 2" and seemed to deteriorate at the same time.
<My guess is starvation. Do try the seaweed sheets. If the snails respond, I'd make sure they were well fed then try to exchange both for a single (much smaller) individual or something else entirely (maybe Cerith snails or perhaps Trochus) at your local fish store. Turbos are unparalleled when it comes to cleaning large swaths of algae, but unfortunately, they can exhaust the available food supply in a hurry and starve to death without supplemental feeding.>
Warmest regards,
<Take care>
Sam Sutton
<Lynn Zurik>

Re: Lethargic Snails: Possible Lack of Food - 5/14/10
Thanks for the prompt reply, Lynn.
<My pleasure, Sam.>
I did have quite a few diatoms (and still have some) and a bit of green algae began to take off as well. I have not added any magnesium as of late, so I think starvation may be the culprit.
<Likely so>
Perhaps the long period (2 months) of a diatom diet led to their current situation. I have quite a bit of dried nori
<Great!>
..and will be sure to try placing it near the snails as suggested. Neither are dead,
<Even better!>
..and if I can get them both to start feeding I will probably see if I can get them over to the LPS before they starve.
<Sounds good>
Would Nassarius snails be a better alternative or should I just scrap the "band-aid" solutions altogether?
<Well, Nassarius snails are scavengers so they won't help with any algae issues. Personally, I'd scrap the band-aid solutions and get to the bottom of the diatom and algae issues. There's a ton of info at WWM regarding both.>
Many thanks,
<You're very welcome.>
Sam Sutton
<Take care, Lynn Z>

10/02/10 Dead Chitons.. No, Limpets!
Hi Simon,
<Hello Beth, how are you?>
My aquariums are doing fine at the moment, thanks to you.
<That's great news!>
Still having a few minor problems with alkalinity and calcium but I am giving it one more water change before I try to address that problem, again.
<Ok. Keep referring to the chemist-man RHF and you should make it through!>
Right now, I am finding dead Chitons in the 20g tank. My big 1 1/2" Chiton is now just an empty shell and this past Sunday I found another Chiton clinging to a rock with what looked like a mucus net surrounding it.
<These are Limpets, not Chitons. They have a conical shell and some have a hole on the top. Chitons are segmented.>
Could the mucus be a defensive mechanism of the Chiton or is it what killed the Chiton?
<This has probably come from the Limpet itself when it died. Did you not think you had a predator of these somewhere?>
It was Super Bowl Sunday and I promised my dad I would watch it with him so I snapped a couple of pictures and ran out the door. When I came home the next day, I found the empty shell of the Chiton lying in the sand.
Any clue as to what is happening to the Chitons?
<I'm sorry Beth, apart from a predator and/ or water chemistry I have no idea. Remember that these need balanced calcium & alkalinity to build their shells. If these have been 'off' for some time, on top of the other
problems that you have had, then that could easily explain their deaths.
Maybe it has all just been 'too much'. Do be sure to test to make sure that you do not end up with a 'cascade' effect that affects your other creatures>
Thank You for your help,
<No problem at all>
Beth
<Simon>

Re Snail Removed From Main Tank, hlth.  10/7/09
Dear WWM Crew and Lynn,
<Victoria>
I have a some more information for Lynn.
<Will pass on to her.>
Snails have continued to die. After removing the killer snail, I placed 5 new snails in the tank, and only one lived. The next day I witnessed Nassarius come out of the sand like zombies to eat the snails added.
<Eating the live snails, or were they dead?>
Mind you I have not seen this happen before, with the previous deaths, and actually have not seen these Nassarius snails in 6 months.
<They do like burrowing in the sand.>
These new snails were sent home in a dry bag, not carefully acclimated. I was very surprised at the dry bag. I have never had snails sent home like this, and just floated the bag a while, added some water, set them in the tank and hoped for the best. Few days later I bought two turbo snails from LFS, carefully acclimated them. I observed them to be active during acclimation and when introduced to the tank. Days later found one laying on side, closed up. The other shell, cleaned out. The shells are found all over, near where I saw them inactive. I do have hermits, maybe 6 tiny things, 3 slightly bigger than tiny. None in the newly dead snails shells.
(My original snail deaths were 4 turbo snails in the tank for 2 years) At this time I placed two of the remaining snails in the refugium as an experiment. I am hoping to discover water quality issue vs. predator.
Perhaps these snails are too far gone. I will just have to wait and see.
I may go get a new snail soon and place it in the fuge also. Any advice would be appreciated.
<I think you are on the right track with the experiment and hopefully eliminate predation and/or water quality as the cause of death. Do keep us informed of your findings.>
Thank you for your help. I greatly appreciate it.
<You're welcome, and will forward this to Lynn who has help so much in this matter. James (Salty Dog)>
Sincerely,
Victoria

Mexican Turbo Snail Digging, hlth.   7/12/09
Hi,
I started my first tank (29 gallon BioCube) about 1 month ago. I cycled the tank with 35 pounds of live rock and 30 pounds of Aragamax sand (approx. 2 inch sand bed). In the last two weeks, I have added 2 A. ocellaris (tank-raised), 1 Mexican Turbo Snail, 1 Cerith snail, and 1 Nassarius snail. Ammonia is low;
<Should be zero>
Nitrate and Nitrite are both zero. When the snails were first added, the Turbo and Cerith went to the top so I adjusted the return nozzle to increase oxygen. Everything seemed fine for a while (the Turbo Snail was eating dried seaweed) but now he has burrowed about half of his shell's length into the sand. I feed him some seaweed today. He ate but he would not come out of the sand. Is he dying or is there a water issue I should test for? Thanks in advance.
<Can't tell from the data presented... I would stay observant, remove the animal if it stops moving, the water starts to smell... Use activated carbon, siphon the area, snail out rather than net it... Bob Fenner>

Re: Some Inputs on Dying Snails Query  12/30/06 Hi everyone! I just want to comment on the problem of the dying snails (original query attached below).  I had this problem before in my fully stocked reef tank, everything was ok, except for the gastropods, who seemed to lose grip and balance, fall down to the gravel, unable to right themselves and dying after a few days.   I teach undergraduate invertebrate zoology, and I soon made a connection between one additive and the gastropod deaths: Magnesium sulfate and Magnesium chloride.  In the lab, either of these compounds is used to slowly anesthetize and 'relax' aquatic invertebrates to allow for easy dissection.  In my case, magnesium overdose was traced to the poor quality sea salt I was using at the time ( I know better now). I shifted to natural seawater for a time, and then used a quality sea salt, and my snail problems have stopped. Magnesium toxicity may also be brought about by dosing (or overdosing) on magnesium supplements.  It just may be that certain gastropods are more sensitive to this compound, become anesthetized, and become so relaxed that they asphyxiate, or otherwise become vulnerable to predators in the tank. I never did any full scale experimentation to prove or isolate Magnesium as the culprit, all I'm saying that it's worth looking into. Hope this little info helps! Best regards, Richard (Manila, Philippines) <Thank you for this. BobF>

Substrate fears and missing Ceriths   2/26/08 Hi: I'm fairly recent to the hobby, but I've read and read the FAQs on WWM, which are a great resource! Now I have a problem I'm not sure is general enough that it's been answered before For setup, I have a 55 gal system with an overflow into about a 15 gal, 3 chambered sump with a too-tiny wet/dry (which I am slowly removing in favor of a filter sock setup which I will change out every other day or so) and a 6 gal remote deep sand bed (just plain sand in a dark bucket fed with a powerhead from the sump and draining back into the sump). The system is 3 months old in the sense that that's how long I've had it running in my house, but it's actually more of a "moved" system, since I got it from someone leaving the hobby who had had it up for about 2 years previous. We removed the remaining livestock (clownfish, a single Astrea/Trochus snail (I still can't always tell which is which) and some hermits), drained most of the water, wrapped the LR in wet newspaper, and then refilled the tank in its new location with fresh mixed water (Instant Ocean). After a very short cycle and some waiting ( I expected the system to be much more unstable, but I guess since it was an old system there was still plenty of living bacteria in the rocks and sand), we eventually removed the homeless livestock back in. All did well. Since cycling, my readings have been all 0 throughout except for a nitrate level that hovers around 15-20. <This will largely go w/ the removal of the wet-dry media> Alk 300, ph 8.2-8.4. I haven't really measured calcium since I don't have any coral yet. Coralline seems to be growing fine. I have a protein skimmer (sea clone, yuck, but fiddling with it all the time, while annoying, seems to at least get it pulling skimmate out steadily), PC lights with actinics and moonlights, and two Koralia circulation fans that keep things moving and suspended. Not sure what else is relevant. <So far, me neither> My return pump is 700pgh which goes into a rectangle pvc rim at the top of the tank with several holes drilled in it, and the fans rate at 800gph and 400 gph. I don't know the poundage of LR, but however much it is, it seems like a bit too much for the tank: not enough open sand for my liking, and hard to get the fans arranged without dead spots or building hills and valleys in the substrate over time. <Take some out... put it in the sump> I've been thinking about selling away a piece or two. I do water changes about once a week, usually 10gal each time (hoping to lower my nitrates), <Mmm, will only help nominally/proportionately... temporarily> though I've been cutting back to 5 gal done more often. I've been using AmQuel+ treated tap water (UK: maybe this is my problem!), but I recently invested in an RO/DI that's putting out 0 TDS, 0 chlorine, 0 anything else I've been able to test, as advertised. For too long I was also using treated tap water for evap top off, but I figure that this is really bad, because, as I realized, benign or no, those chemicals and their bonded bad stuffs can only increase in concentration over time that way. <Mmm, could be bio-accumulated...> Hopefully I've switched soon enough to avoid any serious problem, and my steady 5 gal changes should hopefully dilute, dilute, dilute anything that's built up in the water column (hopefully this stuff doesn't live forever in the rocks and glass). <Nothing, nothing... nothing lasts forever> The substrate is a coarse grain aragonite, though rounded and not sharp, and fairly shallow (an inch or two). The substrate is my major concern however. It is, obviously, old substrate from the previous setup. I have no idea what's lurking down in it in the way of nutrients. One of my big regrets in setting up this system the way I did was not simply replacing the substrate entirely and starting from scratch (I guess we didn't want to wait anymore and let more of the LR die off at the time). I know you can always replace it, but that seems very daunting and dangerous in and of itself. <Nah> And I fear that it's been killing Cerith snails. Over the two months, I've gradually added several Nassarius snails, two small Turbos, one large turbo, and two Ceriths. <Why? I mean, towards what ends the gastropods?> My acclimation process is to float their bag in dark of the sump for temperature and drip acclimate, usually for 3 hours or so, before adding them to the display. All have, as far as I can tell, thrived: they are active and eating well, cleaning glass of both film and even thicker fuzzy green algae in the case of the larger turbo. The two Ceriths, however, moved very little at first, and then died within days (confirmed by smell and not either closing up or coming out). I wasn't sure why, when everything else seemed fine. <Could be a few things... posted> One of the Nassarius, after more than a month in the tank, seemed to become weak, hang out on the glass (is that a diagnosable behavior?), <As itself, no> and seemed to have a little white pus on its underside shell next to its foot (though this could have just been muck from burrowing: hard to tell). It finally was moving enough to turn itself over, but it wouldn't move to take nearby food (a skewered piece of shrimp dipped in on a plastic stick: the other snails swarmed it and sucked it apart). The next day, its shell was empty... except for a small bristleworm cleaning things up. I wish there were better resources for diagnosing snail illness: I enjoy them more than fish, but there seems to be little out there on diseases or common problems: people treat them like disposable "clean up crews" instead of critters. The next sign of trouble was the recent addition of four Cerith snails (each about an inch from head to tip, and a different species than before: the first two were darker and fatter shells, these were long and rocky gray), three weeks ago. Or rather, there were no signs of trouble that I could see... After acclimation, they quickly burrowed into the substrate. I checked every night with a red LED (small bike lights work great!) <Neat tool application> to see them come out: I like to get an eyeball on every major creature in my tank at least once a day to see how its doing. They seemed fine: I couldn't always find all four, but with all the LR I have and the many spaces in the back where there is sand I can't see, that wasn't surprising. They would come out of the sand about an hour after dark, eating at the bottoms of the LR, climbing on it, and once or twice climbing the glass. All were eating and strong enough to stick to the glass even in areas where my circulation fans had strong reflected current. But after a few days there were fewer and fewer sightings, though when I did see one, it seemed fine. In the last two weeks though, I haven't seen any, despite checking at all hours of the night and day (literally). Someone on a message board suggested dropping a sinkable veg pellet in at night, said that their Ceriths would come out and swarm such a thing. Well, my Nassarius went crazy, but no sign of the Ceriths. I've also watched the substrate carefully for any "tracks" that suggest that I was somehow missing them. Nothing: no visible evidence of them coming and out. At this point I'm working under the assumption that they are dead. <I wouldn't be so sure> Which is a problem. What could kill all four of one kind of snail in a tank where everything else seems happy? <... Please read here: http://wetwebmedia.com/snaildisfaqs.htm and the linked files... Could be a chemical imbalance (very common), predator (a bit less common)...> Why wouldn't other snails die or show illness as well? <More tolerant of the root cause/s of mortality...> The Ceriths burrow far deeper into my substrate than the Nas snails (most of which seem to have mostly given up complete submersion), and I'm really worried that what killed them was something toxic down there. I'd like to find their bodies to confirm (and also, if they are dead, to at least have the shells for hermits to try on) that they are dead and maybe some insight into how, but I'm loathe to go poking around in the substrate for fear of stirring up whatever might have killed them. I do have small hermits, but I figure that if they killed them (and they haven't bothered any other snails) that they'd either be wearing their shells already, or at least that the remaining bodies would be above ground rather than nowhere to be found. So now I'm quite worried: worried that I have killer substrate, but having no idea how to confirm it, or what to do about it. There's no "rotten egg" smell I can discern or any other obvious sign. I lightly siphon above substrate to remove debris (some of which is odd: long before the Ceriths I get little discrete piles of fine beige grains, much lighter than diatoms: piles of copepod molts maybe)? And nothing else seems to be in distress. The hermits have been reproducing (shaking what look like live bees off their back), which the clown always quite enjoys, Nas seem to periodically lay their doomed eggs on the glass, which pods probably enjoy, there are red hair worms living in the sand, small bristleworms that come out at night, some peanut worms (maybe? All I ever see are strange pale tubes coming out of sand/rock that seem to suck up bits of things and then you can see it traveling slowly down their length), and for a time even a huge spaghetti worm (with tentacles up to a foot long: this has, much to my disappointment, either since moved out of obvious sight or died). I suppose I could have gotten snails that were all four somehow damaged the same way, or did something wrong acclimating them. <Happens> But there didn't seem to be any problems I could diagnose, and these are the second set of Ceriths (though not the same species) to either die or vanish. Is there something I'm missing about keeping this animal? What should I do to find out what happened to them? Are there any husbandry things I can do, or things I can test or check to find out if I'm at fault? <I would "take a chill pill" here... Not worry, not replace this genus/snail...> I know I went on and on, but you said to be detailed, and I hope I was detailed enough. Thanks for any help. <Enjoy the reading, your system. I might add/switch out some of the old substrate... as recounted on WWM. Bob Fenner>

Turbo spp snails  12/23/07 Hi, I have a 55 gallon salt water tank that I just recently replaced with a new one. (the other on was over 15 years old and looking old). We also moved to a new address so I thought it would be a good time to change the tank. When I planned the move, I bottled reverse Osmosis water and also bottled the actual water from the other tank. I did not add anything new or different. I still had the same live rock, snails, fish, substrate. I did and an undergravel filter which is in addition to the top filter I was using. I moved them and they were only in a bucket for about 2 hours. It has been about two weeks and all my fish survived as well as the smaller Astrea spp. (I think) have all survived, but within just 3-5 days I have 3 maybe 4 of my Turbo spp snails are dying. I don't know what I did, I would have thought the fish would show the first signs but they are fine. The snails are about 1 years old and I got them at the same time. Is that just their life span or is something wrong? Thank you, Linda <Mmm, might be just coincidence... if the Astrea survived... the Turbos should have also. Bob Fenner>

SW Snail Problems... plus    11/30/07 Hello! <Hi there> I've been reading the articles about snail death and cannot seem to find an article that sounds exactly like my problem. I have a 10 gallon tank with 10 lbs of live rock that has been set up for about three and a half weeks now. Every single snail that I have purchased has died within a few days of introducing to the tank. At first, I thought it was an ornery yellow-tail damsel <Needs more room than this...> knocking them off the side of the tank and then nibbling on them (I have since gotten rid of him). I bought one Mexican turbo snail and was advised by my dealer to acclimate him over a half hour, and did so. He was dead within two days. We tested the water which yielded the following results: alkalinity=9 <What units?> pH=8.2 calcium=420 <Magnesium?> nitrates=10 nitrites=0 water temperature=75-77 degrees other critters in the tank: 6 crabs 1 tomato clown 1 watermelon wrasse 1 sand-sifting goby <... none of these fishes can live well or long in this volume> 1 cleaner shrimp all doing wonderfully! <Uh, no> My dealer has told me that because my tank is so new and has natural ocean water, I should not have a magnesium problem. <I would not be... am not... so sure> We are both stumped! Any ideas as to what I should next? Any advice would be greatly appreciated, thanks! All the best, Meg <Please read here: http://www.wetwebmedia.com/snaildisfaqs.htm and the linked files above... AND on WWM re the Systems needs of the other life you list. You need to return the fishes, or get a much larger system... Bob Fenner>

Snails Dying... Check Magnesium and Calcium Levels  10/20/07 Hello Bob, <Nope, you have Mich tonight.> I have run into a little problem with my 90 gallons reef. For some unknown reason, Astraea Snails and Margarita Snails have been dropping like flies lately...literally. They seem to lose grip of the surface and I often find them upside down on the sand. If/when I do see them, I flip them right side up but they eventually pass within days. I've lost about 15 or so snails so far, did everything from water changes to picking off the Pyramidellid snails. Salinity remains stable around 1.025 to 1.026. <I would check your magnesium and calcium levels.> I have noticed parasitic snails on them lately. I pick off as much as I can but am not sure if this is the root cause. <Well certainly isn't helping!> My water parameters seem fine (or so the test kits say) with no traceable levels of ammonia, nitrite, and about 0.5 ppm of nitrate. <There are other important parameters.> I do use RO/DI water and the cartridges are changed below manufacturer's recommendations, except this time the carbon cartridge may have been a bit overused. <OK.> The tank is LPS dominant (very healthy with Xenia Elongata growing like crazy) with 6 Chromis, 2 small Hippo Tangs, 1 Yellow Tang and a Pseudochromis as the only other occupants in the tank besides the corals. I should also mention Mithrax crabs never seem to last long in this tank. Any recommendations? <Yes! In my opinion you have too many tangs on too small a tank for this to last any period of time.> Is this due to the parasitic snails, high chlorine levels due to the carbon cartridge? <Chlorine will be detrimental to your system.> Although snails are not relatively expensive, I hate kill any species of marine life. <How does one place a monetary value on a life?> I wouldn't want to buy more snails until I find the cause of this. Any suggestions? <Yes, though I don't know this for sure, I suspect that this behavior may be associated with elevated levels of magnesium or a magnesium/calcium imbalance. Magnesium is the second most plentiful cation (positively charged ion) and the third most common element in seawater. In plants an imbalance yields a reduction in photosynthesis. In animals magnesium serves an important role in neurochemical transmission and muscular excitability. In humans magnesium salts are often employed a sedatives. Magnesium sulfate for example is employed to reduce the risk of seizures acting to a degree as a muscle relaxant as well. Magnesium Sulfate comes with a risk of circulatory collapse, and the depression of both the cardiac and central nervous systems. In a hospital setting, when magnesium sulfate is given intravenously to a patient the antidote, calcium is kept at the bedside. Elevated magnesium levels are reduced by calcium. So checking your magnesium and calcium levels would be a good place to start.> Thank you! <Welcome! Mich>

Re: Snails Dying... Check Magnesium and Calcium Levels   10/22/07 Thanks for your quick and detailed response Mich! <Oh, you're welcome! Hope it wasn't too much "theory". Sometimes I get on a roll and don't know when to stop! Heehee!> What you said does make sense, something I never would've thought of, that's why you guys are the experts. <Heeee! Some more than others... I'd tend to fall more so in the "others" category, but help out where I can!> I've been using a two part calcium supplement called C-Balance. <OK.> Is it necessary to add calcium only supplements from time to time? <There are a lot of variables here. Some never add calcium because of frequent water changes and low Calcium loads, others continually drip Kalk. So no "right" answer here... other than all depends.> It seems if calcium begins to drop, it may be depleted more easily than magnesium therefore causing the imbalance. <This could be. Would be interesting to study. Mich>

Dead snails 10/16/07 Hello fellow fish lovers, Fist some stats. I have a 55g FOWLR. SKIMMER, FLUVAL 305 CANISTER. SP.GR. 1.026-CAL 400-PHOSP..015-ALK 275PPM-PH 8.3-AMMO. 0.0-SAME FOR NITRITE AND NITRATE. The big question is why are my turbo snails dying???? I bring them home and acclimate them for about an hour and then put them in the QT. Within a day or two they go to the big snail shell in the sky. Have had the tank running for about four months and this is the first s.w. tank I have done. <Are those parameters those of the QT tank or the display tank? are the two the same?> Please help. <Best, Sara M.>

Re: Dead snails... and more  10/16/07 I try very hard to keep both tanks with the same parameters. This morning my chocolate tank was dead. <Chocolate tank?! Now there's an idea! j/k I assume you meant chocolate tang. Sorry for your loss. Just from what you've told me, I don't know why it would die.> I did a complete water test this morning. The only difference was the phos. Was .010 and the Alk was 270. This is on the display tank. <Hmm, snails can be VERY sensitive to salinity, pH and temperature changes. I know you said you acclimated them over an hour, but this might not have been enough. I would try acclimating them in a different way. Take them out of the bag water when you get home and put them in a bowl on top of a paper towel soaked in QT tank water. (Don't make a puddle. The paper towel shouldn't drip). Make sure they retreat completely back into their shells before you put them in the bowl. This squeezes most the water out of them. After you set them on the paper towel in the bowl, wait till they start to come out and move around looking for water. Then put a small amount of QT water in the bowl (not enough to cover them). When they start moving again, add a little more water... and so on and so forth until they're submerged. This allows the snails to have some control over the pace of their own acclimation. Another option is to, instead of putting them in a bowl, stick them to the rim (space permitting) of the aquarium (above the water level) and let them crawl in when they feel like it (this is risky though because they might fall in before they're ready). Good luck, Sara M.> <<Sara... refer... to WWM... Snail hlth. RMF>>

Marine Start Up/Snails Belly Up 9/15/07 Hi <Hi Carroll> I have read a lot on your site before I set up my tank. I wish I would have read the part about hermit crabs before I bought them though. This is a FOWLR tank I have a 29 gallon tank with 3-4 inches of live sand substrate and 13 lbs of live rock cured before I put in my tank. I have a biological wheel that is supposed to handle up to 55 gallon tank. My set up is three weeks old. The live rock had been by itself for a week and half and appears in the last few days to have a rusty brown color to the rock. <Possibly diatoms, usually happens in new systems.> It has not discolored sand or made the tank cloudy. I purchased two turbo snails and 3 smaller snails and 5 hermit crabs to start the cleaner part of the system, no fish in the tank yet. The hermit crabs seem fine but all 5 of the snails have not moved in two days period. The hermits were stuck to a couple of the snails when in the bag. Water temp is about 77.8. Salinity is 1.022. Nitrate 20 Nitrite has gone up since I put the critters in. Alkalinity about 160, pH acceptable after adding marine calcium 1/2 cap. What is wrong with this tank? The snails died right away but the fish store said my water levels were good. <Snails are much more sensitive to ammonia spikes than hermit crabs. Since your tank was in it's cycling stage, I'm guessing ammonia levels were high at the time and caused the death. If your hermit crabs are large, and I'm thinking not, they may have contributed to the loss of your snails.> Thanks for the help. This is a very tough new hobby.! <You're welcome. James (Salty Dog)> Carroll

Any idea what kind of snails these are and are they truly parasitic? - 6/19/07 M Parasitic snails stuck to Marine Turbo 12/3/03 I've attached a photo of one of my snails against the Plexiglas. A couple of these snails ( Turbo ? ) have tiny shells attached to their shells. Could these be yet another type of snail living on my snail. <Argh... these are parasitic snails preying on your larger Gastropods> I doubt that these snails have enough maternal instinct to carry there young around. I am so confused. <they are clearly parasitic to me. Manually remove the small snails when you see them with tweezers. They will wane in time> Thanks, Edward. <best regards, Anthony>

>B >Any idea what kind of snails these are and are they truly parasitic? >M ><Yes and yes. B> Care to share the name? These are not Pyramidelline are they? <Might be> I realize Pyrams are parasitic on clams. But I didn't think on snails. What snail is parasitic on other snails? M <There are MANY! If the gods had particular favoritism for coleopterans (Beetles) and the poor (cuz they made so many of them), they left a little oomph for the gastropods as well... Read on! BobF>

Snail Issues... hlth... env.   6/20/07 Hi, <Hello Emily, Mich here.> Thank you in advance for your help. <You are most welcome!> All but two of my Astria <Astraea> Snails have died in my 90 gallon reef tank. I have a stable system, I test (nitrates, ph, salinity, etc: all ideal) <Vague.> and do water changes weekly. <Very good.> Everything is thriving, but about a month ago I started finding snails down at the bottom of the glass, barely hanging on, like they were very weak. They would remain like this for a couple of days, until they died. <Something may be off in your water chemistry. I would start of with checking you Magnesium/Calcium levels. In humans, Magnesium compounds are used as central nervous system depressants, which reduce muscular excitability. I suspect it has a similar consequence in snails and perhaps this is what you have witnessed. More here: http://www.wetwebmedia.com/snaildisfaqs.htm > When I looked closer there were these tiny little snails (white, long, skinny, pointy) sometimes 20 or 30 up under their shells just hanging on. Can you tell me what they are, and if they are killing my snails? <Many possibilities, and yes I have it on good authority that they could be parasitic. More here: http://www.wetwebmedia.com/snaildisfaqs.htm > And if so, how can I get rid of them? <Tedious manual removal.> This may or may not be related, but I had six very small emerald crabs, and they all died within a couple of days at the same time my snails started dying. <May or may not be related.> I was in my tank, three or four times a day pulling out something dead out. <Ugh... Not a good feeling. I'm sorry for all your losses.> I need to replenish the snails, but do not wish for them to suffer the same fate. <I would hope off on replacement, until issue can be further resolved.> Thanks again,
<Welcome! Mich>
Emily

Snail Problem... Not a Problem  6/10/07 Hey WWM Crew, <Hi Matthew, Mich here.> Be forewarned I'm new at this. <Ok!> But I've been doing lots of reading on your site and I'm sure I've avoided several disasters already. <Excellent!> My tank's been up and running for several months now and today I noticed something is wrong with my snail. See attached photo. <I see.> It looks like it's shriveling up…? Been looking all over the site and can't figure it out. <Mmm, don't think there is anything to worry about here, looks to me like your snail is expelling some waste.> Added a new fish (Yellow Watchman Goby) 3 days ago. So Nitrite = 0 Nitrate 30 <Your Nitrate is getting high, keep an eye on this, and I would consider doing a water change soon.> It's a 40 tall tank with 1 Cleaner shrimp 1 clown fish And a snail/hermit crab clean up crew Help! Matthew <No worries Matthew. Just watch your nitrate levels, and keep reading and learning! Mich>

Re: Snail Problem… Not a Problem… No, is a Problem… - 06/11/07 Hey, <Hello again Matthew, Mich here.> Thanks for responding so quickly. <You're welcome!> Unfortunately the snail is now dead. <Oh no!> I seem to have trouble keeping these guys alive. I bought several from my LFS as part of a clean up crew and all have died. My other type of snail (Nassarius distortus or something similar) are all fine, and the hermit crabs are fine. The LFS wrote it off with a shrug but I don't like my tank being a snail graveyard. <Me neither!> So question one, what the heck is going on? <Mmm, many possibilities here... old age, environmental factors, illness, starvation, predation...> Two, should I replace them? <I would do some water testing before considering replacement. Maybe you should avoid this species in this particular tank.> I have a 40 Tall Eclipse, FOWLR. The tank is fairly new, so far, 5 Nassarius distortus 1 red leg hermit 6 Calcinus laevimanus or similar 1 cleaner shrimp 1 clownfish 1 yellow watchman goby Any and all thoughts would be greatly appreciated, <Perhaps something out of whack with you Magnesium/Calcium balance. Did the snail become lethargic and have a difficult time sticking to the side of your tank? We get queries every once in a while about snails that will not stick to the glass. I suspect this may be related to an elevated magnesium level. In humans, some Magnesium compounds are used as anticonvulsants and play an important role in neurotransmission and muscular excitability. I am not certain that the two are related but I have my suspicions. That's about all I can offer. I'm sorry for you loss. Mich.> Matthew
Re: Snail Problem - 06/11/07
Hey Mich, <Hi there Matthew!> Thanks for all your help, <Welcome!> Thanks for the thoughts on Magnesium, I've since done a WWM search for magnesium with snails and done lots of reading. In one of the emails you responded to it was stated that "a magnesium overdose was traced to the poor quality sea salt" <Hmm, really? Doesn't sound like me. It would be unusual for me to make this type of statement with such certitude.> I'm using "Instant Ocean" and I just ran out today. Is this brand okay or should I be trying to get something else? <I'll quote fellow crew member Jorie here... "If Instant Ocean is good enough for the Shedd Aquarium, then it's good enough for me." This product is generally well regarded.> The snails did seem lethargic and near the end have a difficult time sticking to the side of the tank. At first the part that sticks was white then over a day or two it became a light brown, then they started falling off and dieing. <Sounds familiar.> To have an efficient tank do I need to get something else to replace the dead snails? If so with what? More crabs? Shrimp? Snails? If so what kind? <I believe this was a Turbo snail, which typically grazes on diatoms and microalgae. Astraea snails would have a similar diet. Shrimp are generally scavengers and will not fit the same role and I personally, would avoid the crabs. Hope this helps, Mich>
Re: Snail Problem… Not a Problem… No, is a Problem… - 06/11/07
sorry hit enter, <No worries... I just accidentally hit send without writing a reply! Oops!> one last thought, could it be starvation? <Oh! Yes, absolutely. Is a common cause of snail death.> I don't have any visible form of algae and never have... <This is also a possible explanation. I wouldn't be too quick to replace this snail if you don't have much algae growth.> Thanks again, <You are quite welcome! Mich> ~Matthew
Re: Snail Problem p.s.… Not a Problem… No, is a Problem…   6/13/07
Sorry Mich, I was unclear. <No worries Matt!> I wasn't you that made the statement it was the person who's email you were responding to. (see below) <Ah, yes. I see. Thanks! Hee! I didn't think it sounded like me!> Thanks for all your help. Matt <You are very welcome! Tis a pleasure to be able to help. Good luck to you, my friend! Mich> Re: Some Inputs on Dying Snails Query 12/30/06 Hi everyone! I just want to comment on the problem of the dying snails (original query attached below). I had this problem before in my fully stocked reef tank, everything was ok, except for the gastropods, who seemed to lose grip and balance, fall down to the gravel, unable to right themselves and dying after a few days. I teach undergraduate invertebrate zoology, and I soon made a connection between one additive and the gastropod deaths: Magnesium sulfate and Magnesium chloride. In the lab, either of these compounds is used to slowly anesthetize and 'relax' aquatic invertebrates to allow for easy dissection. In my case, magnesium overdose was traced to the poor quality sea salt I was using at the time ( I know better now). I shifted to natural seawater for a time, and then used a quality sea salt, and my snail problems have stopped. Magnesium toxicity may also be brought about by dosing (or overdosing) on magnesium supplements. It just may be that certain gastropods are more sensitive to this compound, become anesthetized, and become so relaxed that they asphyxiate, or otherwise become vulnerable to predators in the tank. I never did any full scale experimentation to prove or isolate Magnesium as the culprit, all I'm saying that it's worth looking into. Hope this little info helps! Best regards, Richard (Manila, Philippines) <Hi Richard, Mich here. Your hypothesis absolutely makes sense. Magnesium Sulfate (MgSO4) in the human acts as a central nervous system depressant. It blocks neuromuscular transmission by decreasing the amount of acetylcholine released by motor nerve impulses. A secondary effect is the relaxation of smooth muscle tissue. MgSO4 is also the most commonly used tocolytic agent, it decreases the frequency and intensity of uterine contractions associated with preterm labor. It is also used to prevent seizures and convulsions.. Mag toxicity is a huge concern in something the size of a human, let alone a tiny snails. When MgSO4 is given in a hospital setting the antagonist calcium, typically calcium gluconate, is kept at the bedside. Patella Tendon reflexes are continuously monitored for signs of diminished or absent reflexes related to the risk of overdose. So as it relates to the original query, it may be time to check the calcium level and magnesium levels in your tank. The snail death very well may be related to elevated levels of magnesium, which could be reduced by increasing calcium. In the immediacy stop dosing magnesium and increase your calcium levels. Richard, thanks again for contacting us. And to the author of the original query, if you read this please let us know the outcome. All very interesting. Regards Michelle Lemech MS RN>

Algae on My Snail, Causing Me Discomfort - 02/07/2007 <Hi there!  Mich here tonight.> My snail has algae all over it, it can't be good for it.   <It's really not detrimental to it.> What do I do? <If it really bothers you, you can remove it with a little manual manipulation, perhaps with a paper towel.  Hope that helps.  -Mich>

Crabs and Turbos... on their way out    1/15/07 Hello, <Hi there> I currently have a 24G nano set up at my home. I have several fish(3), some peppermints, a cleaner shrimp, a few small corals, Turbos, hermits and an emerald crab and  anemone crab. The tank has been established for one year (next week). I have had pretty good success with the nano since I started it. I do water changes every 10 days, check the water every other day, have good lighting set on a timer, a chiller to keep it at 76 degrees, live sand, live rock, low algae, good coralline algae....just to give you an overview. My question(s) are: 1. I have a  sudden "die off" of turbo. One every 3 days on average. I find them on their backs in the morning, usually being munched on my the hermits or bumblebees. Could it be random?( has a slew of baby Turbos doing very well) <Mmm, being this/too regular... I don't consider random... something is either amiss with your water quality for these snails, and/or a predator is at play... I suspect the crab/s> 2. My anemone crab (who is fairly new) just molted and lost both is large claws and two legs?? <Again... can be water quality (a lacking, imbalance in biomineral (Ca, Mg) and alkalinity... or a predator at play here> He still has his filter feeders, so he might survive? <Yes> 3. My emerald crab lost a claw about 6 months ago and never regrew it. <Okay... I'd be definitely reading up re the imbalance alluded to above... Here: http://wetwebmedia.com/calcalkmar.htm and the linked files above. It is hard to maintain such consistency in smaller volumes as yours... and over time, the more-easily soluble sources in substrates (gravel, rock) are lost... and become rate-limiting... Can replenish to some extent with water changes, feeding/supplementation, but switching out, adding new substrate is the simplest improvement means> His other claw grew very large, but now he has lost it as well. What are his chances? <Fine if no real predators> They need those claws to eat, correct? <Mmm, no... really the smaller set/pair under/behind the largest, forward-most are/can be used here... the biggest pair are for defense and killing...> Anything I can do for him. <Read, understand biomineral, alkalinity chemistry...> Is there anything that might be causing this to happen to my crabs?? Calcium and iodine levels always look good when I test for them. Thanks, Matt <"Looking good"... is of no use here... need numbers, not subjective evaluations. What is your Magnesium? About 3X the Ca? Alkaline reserve measure? Bob Fenner>

Rusty well water, dying snails, need for testing and more reading  1/5/07 Hello! Bob My name is Karl Douville <Hello Karl, My name is Mich and I'll be your WWM Crew member today!> I am contacting you because I have a 180-gallon reef fish tank and my tank does not look the way I always thought it should look like! <Umm OK, how did you think it should look?> It looks pretty healthy but I know something is just not right! <OK.  And you know this how?> I started my tank has been running for 10 month including the cycling period. <OK, still a very young tank.> I have had experience before with the same tank!  On city water. <OK.  Yikes, city water!> I just siphoned my live sand and got a lot of sediments or organic matter, but I'm not sure if it was a good idea, because I was told to not stir up the live sand? <Is good to clean areas of the sandbed, just not the entire sandbed at one time.> My nitrates are still up! About 20 ppm <Higher than desired.> I am using deep well water.  (It has rust in it, but I don't think that is my problem.) <May want to reconsider this.> I don't use R.O. but I did have a really good ultraviolet with three good quality filters! <UV will kill bacterial/microfauna present in water, but will not have any effect on nitrate levels.  RO water should not have any measurable nitrates; the same cannot be said for well water.  Have you tested you well water for nitrates?  How often do you have the wet chemistry of your well water professionally analyzed?> I have done lots of test iron, ph, ammonia, nitrite, nitrate, phosphate and kH gH are all good, but yet to figure out my calcium levels because of an expired test kit witch read way to high to believe. It had no end to the test! <Time to invest in a new Calcium kit.> I have had casualties with snails at the start and I have not bought anymore since that.  (35 snails perished) <That's quite a few.> The snail would be fine in the bag but as soon as put them in they would slither around and then start falling on their backs and I kept flipping them over and over! Some liked the glass but could not go on the sand or they flipped! <I actually suspect you Magnesium levels are too high, possibly having the effect of a muscle relaxant on your snails.  Calcium levels are also likely to be low.  Would be wise to invest in these two tests.>   That's why I thought of the sand being the problem! And I cleaned it! <I don't think this is the problem.> My live sand is 4 inches deep and layered from big shell on the bottom to medium size in the middle and finer aragonite on top!  There has been no hydrogen sulphite bubbles or blackish looking sand. There is not plenum, but I put large shells on the bottom to create natural a plenum. <Would be better to have a 4 inch bed of consistently fine aragonite sand or a deeper bed of the mixed grain.  Please start reading here:   http://www.wetwebmedia.com/deepsandbeds.htm> I have seen copepods, arthropods, worms and none threatening bristle worms (blue and orange) in my sand. <The threat of bristle worms are overrated.> I have 3 cleaner shrimps, several hermit crabs, 2 tomato clowns, 1 yellow tang, 1 camel shrimp, 1 flame angel, 1 algae blenny , assorted mushrooms, small toad stool, some polyps that are doing pretty good and 1 new giant white carpet anemone which is not doing really good.   <Watch the anemone, has the potential to have a large negative effect on your system.> I hope you can diagnose my problem! <Check your magnesium and calcium levels.> Thank you for time! <Welcome, You seem to be missing some key facts here...I recommend you spend some time reading either on the WWM or perhaps invest in a book such as The Conscientious Marine Aquarist by Robert M. Fenner.  -Mich>

Snails Dying 12/25/06 Dear WWW Crew, <Hello> I've been losing snails for a very long time now (over a year). I've read through your articles and FAQs, and haven't found a definitive solution yet. <Mmm> Mid July of this past year, I lost power for almost a week. As these things usually happen, I was away for the week, leaving my wife alone to deal with the problem. Unfortunately, the only thing that survived were some zoos, snails, and obviously some scavengers, since my snails continued to end up as ornaments at the bottom of my tank. The tank has been running semi-fallow since that time, and I'm interested in getting it back to a nicer state. My plan of attack is to set up a whole-house generator, get the remaining algae under control, and then decide on reef or fish, and proceed from there. Unfortunately, I'm not making much headway on the algae elimination because of my snail problem. Please give me some suggestions for how to identify what is causing the loss of my snails. I do see small bristle worms in the tank (do these attack snails?), <Small Bristle Worms shouldn't be a problem in your tank.> but have not heard the snapping sound of mantis shrimp, and have not seen any other pests. One strange item that occurred was that I had an Arrow Crab about a year ago that I found one morning in pieces. <Could very well be from a lack of food.> From what I've read, there's got to be something pretty fierce in there to take out an Arrow crab, but what could it be? If I continue to run the tank fallow and not add any more snails, will the predator eventually starve, or would they be able to live off of things growing in the live rock? <A predator that would attack/eat snails will unlikely survive without a meaty food supply.> How long would be prudent to believe the predator has starved? <If such predator exists, it will gradually get braver in search of food.  If this is the case, it should reveal itself.> What else can I try? I'm considering traps, fresh-dipping all of my live rock, etc, but not sure how drastic to get. <Wouldn't do that.  I'm guessing, based on your info, that your snail population is dying due to a lack of food.  I would remove all but four of five of them and see if they survive.  If algae conditions get worse down the road, try adding another snail, and more if needed, until you reach a balance of food availability vs. your snail population.> My tank is a 75 gallon, with DSB, and lots of live rock. I have a hang on the back refugium. The nutrients in my tank are getting to the point of being so low that the macro algae that has sprouted from the live rock over the past few months grows extremely slowly, the macro in the refugium is not growing well at all, and the hair algae that was a huge issue when I lost power looks like it's suffering. Because of the lack of algae in the refugium, I can see small bristle worms regularly. <Your lack of algae seems to confirm lack of food for the snails.  I'm assuming you haven't treated your tank with any copper based medications or used Windex or similar cleaners near the tank, so this would rule out poisoning.> I appreciate any assistance you can offer me. <You're welcome.  James (Salty Dog)>
Re:  Snails Dying 12/29/06 As always, I appreciate the quick replies. <You're welcome.> I'm attaching 2 pictures of my tank, one from a year ago and the other from this evening. Please review them and let me know whether you still believe that the snails could be dying because of a lack of food. There seems to be tons of algae left in the tank, but maybe they can't live off of certain types? <If the second photo is the most recent...yikes!> Other than food (and not any of that in the past few months) top off water, and additives, I'm not aware of anything else getting into the tank. I add the following: 2 part calcium addition - nearly daily except for days I add other items Kalk - weekly to semiweekly Strontium - weekly Iodine - weekly Magnesium - weekly or semiweekly depending upon test levels The snails dying doesn't seem to coincide with my changing any schedules or anything. Most of the stuff I've used since the tank first cycled 18 months ago and the others were started after the snails started going belly up. Any other thoughts or recommendations would be appreciated. <It appears your tank is loaded with filamentous algae.  In my opinion the Astraea snail does the better job here.  You may want to add one or two Lawnmower Blennies to the tank.  They do a good job cleaning out this type algae.  As far as the snails dying, if you have Astraea snails, this type can actually drown if they loose their footing and end up being completely upside down. They don't right themselves very well.  Other than that, I'm stumped as to why your snails are dying, based on your information.  Maybe one of the crew members may have additional input.  James (Salty Dog)>

Re: Some Inputs on Dying Snails Query  12/30/06 Hi everyone! I just want to comment on the problem of the dying snails (original query attached below).  I had this problem before in my fully stocked reef tank, everything was ok, except for the gastropods, who seemed to lose grip and balance, fall down to the gravel, unable to right themselves and dying after a few days.   I teach undergraduate invertebrate zoology, and I soon made a connection between one additive and the gastropod deaths: Magnesium sulfate and Magnesium chloride.  In the lab, either of these compounds is used to slowly anesthetize and 'relax' aquatic invertebrates to allow for easy dissection.  In my case, magnesium overdose was traced to the poor quality sea salt I was using at the time ( I know better now). I shifted to natural seawater for a time, and then used a quality sea salt, and my snail problems have stopped. Magnesium toxicity may also be brought about by dosing (or overdosing) on magnesium supplements.  It just may be that certain gastropods are more sensitive to this compound, become anesthetized, and become so relaxed that they asphyxiate, or otherwise become vulnerable to predators in the tank. I never did any full scale experimentation to prove or isolate Magnesium as the culprit, all I'm saying that it's worth looking into. Hope this little info helps! Best regards, Richard (Manila, Philippines) <Hi Richard, Mich here. Your hypothesis absolutely makes sense.  Magnesium Sulfate (MgSO4) in  the human acts as a central nervous system depressant.  It blocks  neuromuscular transmission by decreasing the amount of acetylcholine  released by motor nerve impulses.  A secondary effect is the relaxation of  smooth muscle tissue.  MgSO4 is also the most commonly used tocolytic agent, it decreases the frequency and intensity of uterine contractions associated with preterm labor.   It is also used to prevent seizures and convulsions..Mag toxicity is a huge concern in something the size of a human, let alone a tiny snails.   When MgSO4 is given in a hospital setting the antagonist calcium, typically calcium gluconate, is kept at the bedside.  Patella Tendon reflexes are continuously monitored for signs of diminished or absent reflexes related to the risk of overdose.        So as it relates to the original query, it may be time to check the calcium level and magnesium levels in your tank.  The snail death very well 

may be related to elevated levels of magnesium, which could be reduced by increasing calcium. In the immediacy stop dosing magnesium and increase your calcium levels. 
       Richard, thanks again for contacting us.  And to the author of the original query, if you read this please let us know the outcome.  All very interesting. 
Regards Michelle Lemech MS RN> 

Turbo Snails 11/6/06 Hello, <Hi> I am hoping you can help me. I have been searching the web and have found nothing. <Will try.> Yesterday I bought 12 turbo snails for my 55 gallon saltwater aquarium. I don't have any fish in it yet, my first fish are still quarantining. I bought the snails as part of my "clean up crew."   When I put them in, within an hour 10 of them went to work on the  algae, however, 2 stayed in the place where ended up when released from the bag, after acclimation. They are still like that today. A couple websites have said that Turbo snails, when upside down, can't right themselves and will die a slow death, usually within a couple hours. Is this true? <Yes, but may take longer than a couple of hours.> As soon as I read that on one of the websites, I reached my hand into my tank and turned them right side up. So, I guess my questions are 1) Did 2 of my turbo snails die from  being turned upside down overnight? <Maybe, although acclimation and other issues are in play here.> Is that even possible? <Yes> and 2) How can you tell when a turbo snail does, in fact, die? <Check it for movement, and the always fun smell test, take them out and have a smell, you WILL know right away.> Thank you, Sarah <Chris>

Snail growth and toadfish ID.  10/24/06        Hello Crew,    <Danny>                  Thanks for taking the time to read my letter. First off, I have an adult toadfish but I'm having problems getting the exact species name. I have included a picture. <Mmm, not here... have you perused fishbase.org re the Batrachoidids? Is this a tropical West Atlantic species? See Paul Humann and Ned DeLoach's works...> He's given me no problems aside from eating all his tankmates. <Not atypical for the group/family> Second, one of my turbo snails has developed a white cottony growth on his shell. There are two of them and were not part of him when the snail was bought. I picked him up out of the water to get a better picture and the growths held up without water. I don't think there is anything on his shell that would support bacteria or mold growth, so sponges maybe? <Perhaps> Also, I found a growth at the top of the white growth that resembles a feather duster. The (radiole?) from the duster are very similar top what's hanging out ton my snail. I also found the same white growth on one of my filter pads. <What a planet eh? I'm not leaving! Nothing to worry re here>   Thanks,   Daniel <Welcome. Bob Fenner>

Marine Snail Parasites? - 08/07/06 Hi There, <<Howdy>> Fist off, I very much appreciate your website - you have saved me many headaches, and my friendly inhabitants many discomforts. <<We are pleased to know this>> I have looked all over your website, and can't find anything addressing this possible problem I have with a few of my Astrea Snails. <<Okay>> I have a small SW tank (aprox. 25 gallons) with two aqua-cultured percula clowns, some small clams (not Tridacna), feather dusters, sponges, two small starfish, LR with coralline and Caulerpa algae.  As I was doing a water change the other day, I noticed something growing on the shells of a few of my snails.  I wasn't able to get a good picture, but it looks like a black raspberry growing on one side of the snail.  Although, it doesn't really look black, it looks a shade of green. <<Hmm...>> I don't know how long they have been there, but I would imagine they've been in the tank for a while.  Two or three of the snails have large "colonies" on them, and a few others have just a few "bubbles" on their shells.  Everything in the tank is growing and thriving, but I want to make sure I don't have some kind of parasite taking residence on my snails.  Any suggestions as to what these are? <<Impossible to say...but sounds to me like it might be Valonia, or another species of "bubble" algae...may even be a form of coralline growth.  I wouldn't worry much at this stage.  Keep an eye on it and see what develops...or maybe even pluck the organisms from the snail's shells if you wish>> Thanks, Jon <<Regards, EricR>>

Turbo Snail dilemma I have a little problem with the turbo Snails in my tank. I had three nice sized snails and each one of them died the same way? I had one in my tank for almost 5 months and the other two a little over 2 months and one by one they started to die the same way, its like they fall of the glass, I flip them back over, and over a course of a day or two they would stay in one spot and slowly  die. <Do you have any idea of how long they were upside down? That does make a difference.> My nitrate levels are a little high (Nitrate NO-3 range in between 5.0 to  10 on the card) and my PH levels are a slight low but nothing to worry about and the rest of my levels are fine. <Its hard to determine whether its anything to worry about without having the actual numbers but I would say that it could possibly be a combination of the two or fluctuation. You don't mention how long the tank was established? Do you have a lot of algae? Turbos need a lot of algae to eat. I have had some over four years that are thriving and having babies so they can be kept for a long time. Have you kept them for a while before you lose them? Or do they die very quickly? Turbos do best with a long, slow acclimation process.>I have one piece of mushroom coral in my tank  growing off a rock, its the only piece of coral in my tank and its been there  for almost two years. That's why I'm a little confused why my snails are dying.  Maybe you can tell me what's going on I can really use the advice, so when I do  get more snails I won't be wasting money. Thank you so much........ Dave  Nahodil   <Hope this helped Dave or at least gave you some directions to find the answers. MacL>

Turbo Snails... actually nothing, or not much to do with Gastropods... something about setting up a reef tank... No prev. corr. included... I have had my tank for 2 years now, but like I said, I had the one snail  for 5 or 6 months. There is algae in my tank, but it grows on the glass but I   clean it off so my tank looks nice. There is algae all over the sand,   rocks, ornaments. I have just got the Fluval 304 Canister Power Filter to  eliminate the Whisper filters. <Mmm, I'd run all in tandem... at least for a while> I have a lot air pumps and a artificial current  pump for good water circulation, also I have natural ocean sunlight bulbs for  lighting. I have a lot of sponges, baby starfish, small clams, small feather  dusters, and those thin white stringy things growing out of the sand. I also  keep my heat at 80 to 82 degrees in my tank because of the air conditioning. I  want to start a reef tank, but I don't want the coral to die, so if this can sum  up anything for you about my problem please let me know. Thank you Again.......   Dave Nahodil       <? Please keep reading... re the systems for the animals you intend to keep, compatibility... foods/feeding/nutrition... on WWM, elsewhere. Bob Fenner>

Suicide Snails/Shedding Shrimp - 01/24/06 Hi Guys! <<Hello!...and don't forget the gals we have here too...>> I have a 36 gallon SW tank, with about 30 lbs. of live rock.  I have a clownfish and a yellow-tail blue damsel. <<Alright!...glad to see you haven't tried to stuff a couple tangs in here!  Goodonya!>> In addition over the past four months we have had one fire shrimp, three peppermint shrimp, and probably 12-15 snails (fennel & Astrea/turbo) <<Hmm...not saying I'm always the brightest bulb in the box...but the only Fennel snails I'm aware of are the ones that have been seasoned with same, i.e. - Escargots >> -- never more than six at a time) all die. <<Little buggers can be tougher to keep than many folks think.>> The peppermint shrimp didn't seem to last long at all.  The fire shrimp lasted a good couple months, but was molting every two weeks and finally gave up. <<Mmm, yes...metabolic burnout maybe.  Something does appear to be amiss here.>> The snails, however, seem to want to die.  They head straight for the intake valve of the protein skimmer (and subsequently get their guts sucked in...) or just jump off the walls of the tank and can't right themselves. <<An unfortunate design feature of the Astrea snail's shell (when it comes to captive keeping).  These critters are made for rocky/rubble areas where they can easily "right" themselves after a fall...not so easy on a flat sand bed.>> The two fish seem to be thriving, and we even have some corals (what I believe is pimpled mushroom corals) which are growing like crazy and doing very well also.  Any suggestions as to why we can't get the inverts to live? <<A couple thoughts...  Firstly, test your calcium, magnesium, and alkalinity and make sure all are at natural seawater levels/in balance.  Second, make sure to acclimate the snails and shrimp carefully as they tend to be sensitive to changes in osmotic pressure and pH.  And third, try dosing iodine/iodide, making sure to follow directions closely.>> Thanks! Becky <<Regards, EricR>>

Snail Death in Marine Tank  11/28/05 Hi <Hello Glen.> Question.... <Of course.> I found some dead snails... decomposing water has slight smell.. <In your aquarium I assume?> Snail shells I removed smelled.. my nitrates was about 20, <This could be why the snail died or this could be a result of the death, either way needs to be brought down through water changes.> It rose slightly... checked nitrite level .on color chart shows slightly over zero less than 0.25... fish look normal <Yes but it should be zero, I would go ahead with some water changes.> Have protein skimmer and U.V... I also rinsed the filter off, kept bio wheel intact and untouched... should I do a water change <Yes.> First thing in am .. if so how much  <A few large (at least 25%) consecutive changes until water chemistry is at par.> yesterday I did a I 5 gallon water change 30 gallon tank.. but that was before I n noticed the dead snails.. in the tank <Were they new, snails are quite sensitive to acclimation, if not the nitrate levels, should be as close to zero as possible for inverts and nitrite levels, should be zero…period, are to blame.> Thank u for your help <<"You", not "u".  Marina>> <Welcome.> glen <Adam J.> 

Hair Algae/Dying Snails - 07/17/05 I have a 75 gallon tank and fifteen pounds of green hair algae! <<Mmm, been there before myself...>> Ok, I cannot get rid of this stuff.  I only have one clown fish and a cleaner shrimp. a bunch of scarlet and blue hermits...I have tried everything...every time I add snails they die off. <<Yikes!  This is telling you something...>> I don't know if it is the larger crabs killing them or what. <<Maybe...but likely the "or what.">> Would a UV Sterilizer help here? <<I doubt it.  Not to say these devices don't have/serve a purpose, I just consider them too high-maintenance and of limited benefit in marine systems.  You're better served with an ozone generator in my opinion.  Though this is not necessarily the solution to your problem.>> Should I remove all 90 lbs of my live rock and put it in a tub with a power jet in the dark? <<Is an option...though for the benefit of any photosynthetic life on the rock you might do better to remove, "gently" scrub in clean salt water, and place back in the tank.>> I had a great tank but everything died off except what I mentioned. <<???!!!... Did you determine/correct whatever caused the die-off?  This may be the source of your algae problem.>> I recently replaced about a 3rd of the substrate and that didn't do it either. <<Wouldn't expect it to.>> I think it may be my skimmer...it doesn't produce much and I have to baby-sit the darn thing to keep it working....if I got a new skimmer would it do the trick? <<A quality skimmer can definitely help and should be your first purchase before a UV or ozone unit (ER, Aqua-C, and ASM are good skimmers to research).>> How frequently should I scrape this and do water changes? <<Likely weekly to bi-weekly.>> Is there an additive I can use? <<No magic elixirs I'm afraid.>> Is calcium good or bad in this instance (as in dosing Kalkwasser)? <<Calcium is good...the addition of Kalkwasser can also help by raising/boosting pH and precipitating phosphate.>> Help- I am at my wits end with this stuff! <<Make sure your calcium and alkalinity are where they should be (might even boost the calcium just a bit), use Kalkwasser for evaporation replacement, add a "quality" skimmer (try running the skimmer a bit "wet" for a couple weeks), and try to keep your pH in the 8.4-8.6 range...If simple nutrient export is the issue this may alleviate your problem (along with prudent feeding, water changes, et al).  If not, you're back to just treating the symptom and will need to determine what is feeding your algae (that "tank die-off" is bothering me...didn't suddenly change salt mixes did you?).>> Thanks! Jeff <<Regards, Eric R.>>

- Quarantine of Snails - I have a quick question for you guys.  I have a new tank, about 3 weeks old, but it is stocked with 75% mature live rock that has been in an another aquarium for a couple years.  The only livestock in there are a few Zoanthid polyps and three turbo snails that can't really keep up with the variety and quantity of algae growing.  My next additions are a small number of Nassarius, bumblebee, and  Trochus snails, and I wonder if I should keep them in a quarantine first. <I know Anthony would say yes, but I say no... go ahead and put them in.> I know that is the standard of good health, but I can't help but think that the snails are better off in an environment full of sand, rocks, and food for them rather than an empty quarantine tank where I would have to feed them with outside food. <And I would agree.> Because there are no fish in the tank, is there any danger in moving them directly to the main tank? <Generally speaking, fish diseases aren't spread by snails. Only snail diseases would be spread by snails so there is risk, but then again snails are easily replaced and don't seem to hurt as much when you lose one or two compared with a prized fish.> Thanks in advance, Joel <Cheers, J -- >

Turbo snail deaths Hi, I know this question was partly answered but could you give me some detail? Sorry if I'm wasting your time. I have a 40 gallon reef tank with two clownfish, a couple redlegs and a Foxface Rabbitfish and it's going great except for one thing, every turbo snail I add snuffs it within a few days. The guys at a renowned shop said that the water sample I bought in was fantastic and were at a loose end as to what could be causing these deaths. Could my salinity be to blame? There is one turbo snail who I have had for ages and he's doing great, it's just the others that I add which seem to die. <Aaron, one thing to be careful of is, when acclimating Turbos, care has to be taken so they are not upside down when they are put in your tank.  Turbos can actually drown this way.  Other than that, unless you are using some form of copper in the tank, I really don't know what to tell you.  James (Salty Dog) Thanks. Aaron A. Mysterious Snail Deaths... Dear Reefers, <Scott F. your reefer tonight!> I have a 2 foot all glass tank which I acquired second hand over 2 years ago. I use it as a permanent quarantine set up and it has been running for over 18 months, with a water change each week using 7 litres of water taken from my reef system. The tank contains some live rock with Xenia, but no sand. The hardware in the tank is an Eheim pump, attached to an outside canister with sintered glass ring medium for adaptable bio function, and a Polyfilter pad put in as a precaution. There is also a submerged heater connected to an exterior thermostat. It is lit by 2 x T8 Triton tubes with reflectors. I am a natural aquarist, so no skimmer on either system.  <This sounds like a wonderful system to "harden" newly arrived livestock and provide a period of time for you to observe your fish before placing them in the display. However, in my personal opinion, a quarantine system need not be a permanent feature. It's a bare (with the exception of some inert materials such as PVC sections for new fishes to hide in) and temporary; you simply set it up when required and break it down when done. The biggest problem with a "permanent" quarantine system, IMO, is that any diseases brought in with new arrivals can remain in a tank with substrate and live rock, and pass them on to the next batch of fishes. In addition, it is somewhat problematic to treat sick fishes in such a setup, which can render many medications less effective, literally "absorbing" some. Please re-think this setup.> At present there are a few Stomatella snails, Gammarus shrimp, some Spionid worms and a few small annelid worms. There used to be some small Dove snails, but these appear to have stopped breeding and died out. My problem is that I have lost a number of snails during quarantine, the most recent being a large Trochus after about 3 and a half weeks. I have had a similar snail in the main system for over a year, and the other Astrea and Cerith snails in the main system are also all early additions over a year "old". I was about to order some additional snails from a UK mail order supplier, Ultimate Aquatics, and I noticed their warning that these snails are VERY sensitive to copper. <True, many snails are sensitive to copper (yet another reason not to utilize them in any system destined to quarantine/treat fishes!) and other medications.> Could there have been a residue of copper in the all glass/silicone tank when I acquired it, and if so could there still be a harmful level of copper after all this time. If so, why did it not harm the early snail additions during their quarantine? <It is possible, but if the system has been running for some time, it seems unlikely to me that residual copper could be continuing to leach in levels that could be toxic. Keep in mind that many snails are sensitive to environmental changes, and careful acclimation is required to avoid losses.> If not, what could be the difference between the main and quarantine system which is apparently causing snail fatalities? All the measurable parameters are identical, and fishes, corals and hermits have all been through the their 4 week quarantine without problems. I do use a long acclimatization period of up to 2 hours for snails, and I make sure that the snails are not pulled off the surface but teased off. There is food in the form of diatoms on the glass and rock as well as the usual turf algae. <Could be a lot of possibilities, such as a disease or some sort of toxin., or even a predator of some sort that has escaped detection. I've seen such a phenomenon before with snails, and it's hard to say what the real answer is. It can also be source or stresses the animals encountered along the chain of custody from reef to hobbyist.> I would really appreciate your advice on what precautions to take before I order my next batch of snails and try again.. Regards, Eric B  <Well, Eric- I think I'd do two things: First, if you're suspicious about copper levels in the system, I'd encourage you to test for copper in the tank water. Also, you might want to consider acquiring the snails from a different source, to see if there is any correlation between the source and the problems that you are encountering. With a little experimentation and the process of elimination, you might just solve the mystery! Good luck! Regards, Scott F.> 

Nassarius Snails are dying Hello Bob, I really enjoy reading up on the website and have already learned so much. But I am encountering a very frustrating problem. I have a 30 gal saltwater tank, with 32 lbs of live rock, about a 3-4 in live sand bed, two small percula clowns, 8 red tip reef hermits, 10 Astrea (I think that's what they are) snails, 10 Nassarius snails, and two peppermint shrimp.  Well in the past two weeks FOUR of my Nassarius snails have died. They are very tiny, the smallest things in the tank, and seem to be the only thing affected. I have checked and double checked and checked once again my water param.s, and my water quality is very good (don't have a heavy bio-load). But one day I came home to find two empty Nassarius snail shells. I don't know what killed them, just saw the clean-up crew doing their thing. I called up my local fish store, and the person I talked to basically chalked it up to one of the hermits (even though I did not SEE the hermit doing it). Although he admitted it was out of character for them to become aggressive like that (they have them set up together at the store and don't have a problem).  I continued like normal with feeding (once a day in the evenings) and regular maintenance. A few days later I lost another one. This time chunks of him were still in the shell, but once again the clean up crew (this time a peppermint) was cleaning out the old shell. I called the fish store again, the different person I got had no clue as to what was affecting them. I made sure the little guys were in fact eating at supper time and everyone was getting a bite to eat (from the ones I could see out of the sand).  Yesterday was the first day I found one not already dead. He was in the middle of the tank and not moving (as you know, very uncommon for these active little snails) or being harassed by any other tank mates, so I picked him up to check him out, I saw him moving slowly in his shell, I couldn't tell if he was "tore up" from something getting at him or not. I placed him in a less-trafficked area of the tank and this morning he has not moved from that spot. Even if he is still alive. I called the fish store last night and talked to yet ANOTHER person, who can only think of perhaps a bristleworm is doing its work here or some malice hitchhiker crab. I DID have a bristleworm on a piece of rock I picked out when I first setup my tank the day after Christmas, but they removed it at the fish store, could there be more? < I hope so, you want lots of bristleworms in your tank. >  Could any of the salt build-up around the rim of the tank be affecting these guys when the climb the glass to feed on the food floating... < I doubt it, but maybe. I'm surprised they climb up to get floating food. >  ... on the top (which is very interesting to watch!)? Any help would be much appreciated, I seem to have everyone stumped on this and as a beginner I don't know what to think. I just hate to keep losing these snails and not know what it is or be able to help. < Well I wouldn't be worried by this. I'm thinking it may be a lack of food, or they were in poor health from shipping when you received them, or maybe they are just old and died. Either way losing some snails doesn't concern me. When you lose all your snails in an afternoon, then we have a problem. Just relax and keep and eye out. Hopefully this won't continue. > Thanks so much, Christine < Blundell > 

- Snails Dying - All my other inverts, corals, and fish are doing fine in my 29 gallon tank.  The test results have all my chem.s right where they should bell.  My turbo snails seem to be dying for no reason.  I just find about 1 a week on the bed of the tank.  I figure my hermits are cleaning them out..  I feed enough for all inhabitants..  Any ideas?? <Is pretty typical for snails... they fall down, can't right themselves and then either die in place or a hermit crab will arrive and dispatch them.> Would really appreciate it. <I wouldn't load up on snails if I were you... just keep one or two around in this tank and things will be fine.> Mark <Cheers, J -- >

Super Tongan Nassarius Snails dying Okay, a little update, I don't know what it means though. I took a closer look at the little "injured" snail, he is still alive this afternoon.  I picked him up to have a closer look, it seems his "foot" is damaged, all shriveled up and a little shreddy looking (might even look "rotten" but he's so small it's hard to tell). He doesn't have the big beautiful flat foot they normally do, it's more of a thin stump and he retracts it quickly...as if it "hurts"?   I am wondering can the salt be doing this or something attacking them?  It is bugging me to see them suffer like this.  Will you folks reply in email or on the website? I am afraid I cannot navigate the website easily and I don't want to miss the answer. and if it IS already on the website, may I have a direct link?  <Christine, I really have to believe something in your tank is trying to make a meal of these guys. Bristle worms can sometimes do this depending on the species. More than likely it is probably a night time critter that you don't see. I would take out the specimens you have left and even keep them in a glass of water, putting in a piece of flake food or whatever and change the water in the glass daily with tank water. Just exchange the water, no need to make any up. Keep your eye open at night if your able, and use a flashlight and see if you can see anything unusual present in the tank after hours. These critters are fairly hardy so I'm thinking whatever is happening isn't natural. Good luck. James (Salty Dog)>

Super Tongan Nassarius Snails dying - UPDATE 2/25/05 Okay, a little update, I don't know what it means though.  I took a closer look at the little "injured" snail, he is still alive this afternoon. I picked him up to have a closer look, it seems his "foot" is damaged, all shriveled up and a little shreddy looking (might even look "rotten" but he's so small it's hard to tell). He doesn't have the big beautiful flat foot they normally do, it's more of a thin stump and he retracts it quickly...as if it "hurts"? I am wondering can the salt be doing this or something attacking them?  <could be... they are sensitive to water chemistry> It is bugging me to see them suffer like this.  Will you folks reply in email or on the website?  <both> I am afraid I cannot navigate the website easily and I don't want to miss the answer. and if it IS already on the website, may I have a direct link?  <do some keyword searches my friend and learn so much more in the process. Search for "snails shock", "snails sea salt", etc> Thanks again for all your help. <best of luck/life! Anthony>

New 55 gallon Snail and Shrimp Deaths (12-13-04) Hi WWM crew, <Hello. You have Leslie here this evening.> I recently set up a 55 gallon reef tank about 2 weeks ago. I have 60 lbs of Arag-alive Bahamas oolite, 45 lbs of Fiji live rock from LiveAquaria.com which took 5 days to cure, a sand sifting star, 2 peppermint shrimp but one died 2 days after I put it in, 12 red leg hermits, 3 blue leg, 15 turbo snails (about 6 aren't moving so I put them in a separate container and took out the ones that where stuck to the side. 4 I think are dead. they smell pretty bad). My equip. is 260 watt Coralife lunar Aqualight, Eheim pro II 2026, aqua c remora which I set up about 2 days ago, and a Rio 800 power head. I filled my tank up with freshwater from my faucet (well water that passes through 2 carbon filters and a water softener) and mixed the right amount of salt to it. I waited 2 days and check all of the levels. Then I added my sand which I opened the bags underwater and I spread it around. I waited 2 days then added my live rock to the tank. There were still some coralline algae on it since it took 5 days to cure. I set my light system for the actinic for 14 hrs and my daylight for 12 hrs. It ran for 4 days and then I added 10 Turbos, 10 red legs, the sand sifter, and the shrimp. I started adding coral-vital to speed up the growth of my coralline. I did a 25% water change with RO water I got from my LFS which I work at, because my phosphates were .5. I started getting brown algae on my substrate and live rock in a few places, then on the glass. About a week later my substrate was all brown and so was the live rock, on the glass were patches of algae and this single hair like matter about 1/2 long on the glass all over. Over 3 days my water started to get cloudy, on the 3rd day I couldn't see the power head in the back of the tank. the first 10 inches from the top was like white cloudy water and as it went closer towards the sand it become a yellowish-brown like a urine color. all my levels are fine I have been testing my water everyday) I bought the skimmer right after I came home from school and I saw this and I got next day shipping so I received it the next day. It has been running for about 3 days and the foam is white and it produces about 1/2 cup full of brown water everyday (I have it on the lowest setting collecting as much as it can, otherwise I get nothing.) I don't know if the snails that I think died caused this or the coral-vital. I put a bag of Phos-guard, Chemi-pure, and reef carbon in the filter. What could be causing this? Thanks Joe   <It sounds to me like the snails and shrimp were added too soon. If I read the sequence of events correctly you added the snails 6 days after you set the tank up. Your tank did not have time to establishing a biological filter. Please review following articles on biological filtration and cycling http://www.wetwebmedia.com/marine/setup/filtration/biological/biofiltr.htm http://www.wetwebmedia.com/estbiofiltmar.htm> HTH, Leslie All snails dead My 115 G reef tank (90G display + 10 G refugium + 15 G sump) has been running since late August 04. Its inhabitants up until my problem, which I'll explain in a moment, were: 2 green Chromis 1 lawnmower blenny 5 Trochus snails 7 Turbos 30 red-legged hermits 12 Nassarius snails 25 Ceriths snails 12 Astrea snails 8 margarita snails The fuge also had eight mangroves, <Eight? Too many... you are aware how big these plants grow?> Caulerpa prolifera, Chaetomorpha, and Red Grape Caulerpa. The display had green star polyps, and red and green mushrooms. The aquarium runs between 78 and 80 degrees. pH of 8.3-8.4. Ammonia and nitrite at 0. Nitrate below 5. Salinity 1.025. KH 9.6. No phosphate. Calcium has consistently been above 500. <Too high... 350 to 400 is better, more sustainable... particularly in the face of trying to maintain alkaline reserve> I have a Kalkwasser reactor that does automatic top off. I run 2 250W 10K MH and two 48" VHO blue Actinics. On 5 November, I removed Kalk from the reactor to try and get the calcium down, even though it did not seem to have any negative effect. On the next day, I added a purple Montipora frag and a toadstool leather coral. On 7 Nov, I noticed that the Turbos were dormant. None were dead, but they were not moving much. The leather had shrunk a lot and the Montipora turned a dark color. On 10 Nov, I changed carbon, replacing the 1.5 cups with new carbon. I usually run two bags of 1.5 cups each and only change one at a time. I also do 15-20% RO/DI water changes per week, matching temp and salinity. Later that day, the Montipora died. By the 14th, I noticed more snails were dying and the green star polyps remained closed. Somewhere around this time, the leather began developing scabs in its edges. At this point, all snails are dead. The hermits and fish are OK. <Good clues, input, records> One other thing I noticed was the Red Grape Caulerpa was losing its color. <Likely related to the loss of integrity of the chemistry, physics of the environment overall> The Chaeto was also becoming "loose" and instead of a rich green, was more faded. The Caulerpa prolifera, which had been growing like crazy, also began to slow and eventually deteriorate. I removed the Caulerpa around the 20th before they disintegrated completely. Theories include salinity that was way off. That did not pan out because I bought a refractometer and my hydrometer is not off that much. Another theory is copper or brass poisoning, but I do not know of a source that would be causing this. I do use a standard plumbing check valve on the incoming part of my RO/DI, and some standard garden hose bibs to connect a pump to the chiller. Other theory: The Caulerpa poisoned the whole system when it began to fall apart. <Not likely, though a minor possible adjunct> I am open to other theories and ideas. I'd like to avoid this happening in the future again. Martin <Martin, it is obvious you care deeply, have some understanding of basic marine aquariology, and have a BUNCH of money invested in gear... but also apparent that some basic "hands-on" information has not been gained as yet... The problem you had is very likely a matter of a "cascade effect" originating with the super-normal calcium concentration (pushed by your Kalkwasser use)... to put the situation in simple terms, the overabundance of calcium hydroxide (Kalk) diminished the presence of carbonate (alkalinity) and its availability to your snails... AND likely poisoned your Mangrove "stand"... these organisms dying, have precipitated the other observable stress, loss of life. Please take the time to read over the materials archived on our site, www.WetWebMedia.com on: Mangroves, Alkalinity and Calcium, Environmental Disease... in the meanwhile, do NOT buy, place any more livestock or purchase more equipment... What you have, a good mind, capacity to learn, desire to do well... is all you need. Bob Fenner> WWM FAQ - Snails Dying Good evening CREW! <Howdy John, MacL here with you this lovely evening.>   I have read several of your responses on WWM regarding snails. One peaked my interest, as I have had several of my "cleaning" inverts die-off over the last month.  First the basics. I have 55 gal FOWLR. (approx. 60 lbs LR & approx. 40 lbs LS/crushed coral) [2nd running - been up since 26 Apr 2004] Emperor 400 Bio-wheel filter with activated carbon, Aqua-C Remora Skimmer,2-Maxijet 900 Powerheads, and heater. Temp: 76.5, pH: 8.2 Salinity: 32 ppt or approx. 1.024 SG Nitrite: 0 Ammonia: 0 Nitrate: 20 ppm <Lil high I'd like to see it ideally at 0> Inhabitants: 3 - Yellow tail Damsels 1 - Canary Wrasse 1 - Lawnmower Blenny 2 - Feather Dusters I HAD... 6 - Turbo Snails (all died), 6 - Trochus Snails (all died), 8 - Blue Leg crabs (all but one died), 8 - Red Leg crabs (all died), and finally 4 - Peppermint Shrimp (all died). <Did they all die at once? Did they die upon acclimation? Did they die in some kind of sequence?>   Now, back to my question/problem.  I noticed in one of the responses about dying snails, "metals" were mentioned and the artificial salt used might be a culprit.  I am using Oceanic Natural Sea Salt Mix.  The label states "High calcium and magnesium concentrations provide optimal growth for fish and invertebrates."  <I have to say I tried Oceanic and liked it very much.> Could HIGH MAGNESIUM levels be causing my inverts to die? <I really don't think its likely but you can find magnesium test kits. I would suggest running a PolyFilter somewhere in your system to see if it picks up anything that shouldn't be there. Turbos die by falling on their back and they can't get up. Ph swings can possibly kill some of the others. I'd like to investigate this more fully.> I have had two (really one very long outbreak of diatoms) and can't seem to get rid of them either (the outbreak is still in my tank.)  Don't know if that might give you a clue or not, but thought I would mention it. <Diatoms drive me insane the only thing that works for me is Kalkwasser.>   I don't want to get more inverts just to have them die off.  Any help or advice will be greatly appreciated. <Lets not add any until we figure out what it is. One way to test if they die as soon as they get into the tank would be to mix up some salt water and put the invertebrates straight into that instead of into the tank. See if its the saltwater or something in the tank. MacL> John McKnight PS:  Great Job!  with the site.   Refer to it often and find it very useful. <Thank you kindly I will pass on the word.>

Are High Nitrates Killing my Snails? Greetings, I've got a 110-gal saltwater tank with 2-blue actinic and 2-white 48" VHO lights.  The blue's run from noon to 10, and the whites start an hour after and stop an hour before the blues (1pm - 9pm).  This tank has some mushroom anemones, red brain coral, some polyps, 3 Clarkii's, 3 Chromis, a Yellow Tang and a Flame Angel.  All get along great and seem happy, but I would love to add more fish as I'm pretty sure I have room.  Can you recommend something that is pretty and would play well with the others? << Maybe a wrasse or Dottyback.  Also, just about any goby and blenny would do well. >> My other tank is a 10-gal that hasn't ever had anything in it and I'm wondering what I could put in there that would look pretty and be relatively easy to keep in a smaller system. << Again, most gobies and blennies are you best options here. >> I would love a Condylactis anemone and a percula clown, but I'm not sure that this would be recommended.  What do you think?  << I've seen some very successful tanks that were 10 gal Anemonefish tanks.  If you keep it well stocked and clean, it is a good way to go. >> My Turbo Snails seem to die off pretty quickly, yet my other, smaller snails (Ana-somethings) are very hardy and I don't think I've lost a single one.  My Nitrates are on the high end (~20 ppm), do you think this could cause them significant problems with my Turbo Snails?  << It could be.  Or it is possible that the dying snails are contributing to the high nitrates.  Either way, a water change and increased filtration is the best advice. >> I'm setting up my skimmer again, so that should help. << Definitely >> Thanks again for all your great advice.  I sure appreciate it. Sincerely, << Good luck. >> Judd <<  Blundell  >>

Snail Behavior (6/2/04)   Oh Salty Ones a bit of information pls.  Am a daily reader and fan.  You guys run an incredibly fantastic web site!!  <A pleasure to play a small part. Steve Allen with you tonight.> I have started a new marine tank which will be essentially fish only but with a deep sand bed and live rock.  I have an 80 gal. tank with wet and dry and a protein skimmer running (Aqua C Remora Pro). <Excellent skimmer choice.> Also running charcoal.  Have approx 50lbs live rock, mostly Fiji and about 30lbs dead or base rock. <Will "come alive" in due time.> Tank has been running w/o any life for several months, added the live rock about three weeks ago. <Very good. Patience is your ally. If I could change anything about the way I went about starting my tank, it would be to run it fishless for at least 6 months.> Current Stats Temp = 81 deg f Salin =  1.023/24 PH    =   8.4 NH4 =   0 NO2 =  0 NO3 =  0 Alk test kit is not quantitative but reads to the high side All tests by Red Sea Marine Lab test kits but essentially verified by f/u at LFS. <Consider a better kit, like Salifert.>   So I decided to add 5 snails, all whom are supposed to be grazers.  Four "Atlantic Grazers" ??? which are nickel size pyramidal snails that resemble Cerith snails <Almost certainly Astraea from the Atlantic.> and 1 "Teakwell"??? <Never heard this term> snail that is a much larger pyramidal form snail that I suspect is a species of Turbo snail. <sounds likely> LFS did not know such things as scientific names. <They often don't--what a shame.> Placed snails in the tank in different areas after standard acclimation procedure <remember that all invertebrates need a longer acclimation than fish. They are much more osmotically brittle.> (all acclimation water discarded).  Within 4 to 5 hours the turbo type was on the front glass hanging out just beneath the water line cruising around the perimeter of the tank.  On the following day two of the Cerith types were on the glass doing the same thing.  One of the other is on the rock and another is on the substrate.  My concern is with the guys on the glass at the W/L.   They move to an fro but appear to stay near the W/L. I am wondering why they are behaving in this manner. Any thoughts would be appreciated. A struggling neophyte. Keith <Most of the marine snails sold as grazers live near the surface in nature, and some actually need to be out of the water for some period of time each day. Just make sure it's difficult for them to actually get out of the tank. As long as they don't, they'll find their way back to the water. Probably the biggest problem you'll have with these pyramidal-shape snails is their inability to right themselves if the fall on their backs in your sand. I check my tank daily and use and aquarium tong to right the upside-down ones before the starve or get eaten by some opportunist looking for a hapless/vulnerable meal. There is a series of useful articles about grazing snails in the online Mag www.reefkeeping.com starting with the May 04 issue.>

Snails On The Run?  Most all my Turbo, Cerith and Nassarius snails are climbing to the top of my tank, right at the water line, and staying there. Is that normal or is there a problem with my water? I have stuff, debris on the sand from the live rock and I want my critters munching on that stuff, will they?  <Well, the snails that you mention are generally feeders on algae and some organic detritus. If the "stuff" that you are referring to falls into this category, these animals will generally eat these items>  The hermit crabs are on the rock and the snails are at the surface??!?  <Well, depending upon the types of hermit crabs that you have- this could be the reason that the snails are at the surface! Some crabs can aggressively pick at and harass snails. On the other hand, do run some basic water tests to assure that water quality is up to par.>  Its very hard to vacuum the sand because the sand is so fine plus it circulates and eventually ends up under rock with is also hard to vacuum (the debris that is ((is that detritus?)) )  <Sounds like you're talking about detritus here!>  Thanks, Mark  <You're welcome, Mark. I'd observe the tank a bit more closely, to see if your snails have been harassed or preyed upon by other creatures in the tank. Again, do check those water parameters to verify that everything is in line...Good luck! Regards, Scott F.>

Why do snails die upside down on sand? and ID of clear fuzzy stuff 4/9/04  Hey guys,  <cheers, Kevin>  Hope your having a great day, I am.  <very good to hear. I will be too once the hula girls and dwarves arrive>  I have a 75 gal tank with 80 lbs of live rock its been up and running since January. Ammonia 0, Nitrite 0 and Nitrate 0. Temp 77 - 80. you know the basics. I have a 20 gal sump with skimmer and Mag filter with carbon. I have 2 O. Clown, 1 Royal Gramma, 1 Six Line Wrasse, Cleaner Shrimp and clean up crew of snails, crabs and 1 star fish. They are all doing very well, except for dumb snails that fail upside down and die before I find them.  <this is a species selection mistake... you clearly have Astraea Turbo snails (from the Atlantic rocky habitats and unable to survive on fine/soft substrates). Instead, what you need is Turban species (AKA Mexican Turbos) of turbo snails from the Pacific which can easily right themselves from soft substrates. Do let your merchant know this to help them to help others>  But, Lately I have had this clearish white fuzz growing on my rock, what is it? My snails eat it fine but would like to know what it is. Thanks for you ideas? Kevin  <it's tough for me to say from such a brief and general description. If you can send a clear and close photo, I can likely ID it. In the meantime, please do use/browse our wetwebmedia.com archives for algae FAQs, images and articles. Anthony>

Spawning Snails? Hello and thank you for your help. I have an urgent question. In my 280 gallon reef I have perhaps 25 or more Astrea snails. They appear to be mass spewing, some letting out clouds of smoky (sperm?) and others pumping there bodies and releasing clouds of small white dots (eggs) The water is clouding. Will this continue (its evening- tank is in office- Am heading home) Will it hurt the other inverts and fish? Will babies come of it? How hasty should I be In doing a water change and how common is such an event? (Am hoping it is an event lol) thank you again. Brian <Well, Brian, Strombus and Turbo spawning events are becoming more common all of the time, and Astrea are known to have done this, too. It is still not an everyday event, and well worth documenting and recording the event for future reference. Generally, the release of gametes will not degrade water quality, but it is certainly worth keeping an eye on it. In theory, the gametes released by these animals during the spawning can serve as a form of plankton for your filter feeders.  If water quality appears to be suffering, then by all means, accelerate your water change schedule. Otherwise, just follow your normal schedule. It's unlikely that many of the young will appear, but you never know...Keep an eye on things- good luck! Regards, Scott F.>

Snails leaving their shells: check water quality! 12/14/03 Hello guys,  First let me tell you how much I love the site.  I have spent many, many hours cruising the vast knowledge contained here.  I always find the answers I am looking for to help me be more successful in my aquarium husbandry practices.   <ahh, good to hear> But I have one that has stumped me and I can't find any postings with the answer I am looking for. My snails seem to be leaving their shells and the Cerith snails that have kept their shells are trying to climb out of the tank.  It seems as if there is something irritating them that they are trying to get away from. <quite likely a water quality issue... do consider a large water change ASAP. Amy change in sea salt brand recently?> My first thought was that some parasite had gotten in the shell and was pushing them out.   <not likely at all> This first started when I had a run in with jacked up calcium and alkalinity levels.  The calcium reached upwards of 600 and alkalinity fell to 6.  I don't care to expand on the cause of this but it was due to my misunderstanding of the use of Kalkwasser.  I chalk it up to a definite learning experience.  I have corrected this problem and now Ca is at about 450 and Alk is at 8-9 (seems a little high considering the Ca level but I have not had a snow storm or anything).  All of my water parameters seem to be within the specs. I don't know if the calcium levels were just so high that it wasn't useable to the snails, which in turn would not allow the shell to grow with them. <hmmm... more likely just the stress of extreme and fluctuating water quality> Other than being shell-less the snails seem to be quite healthy, and the Ceriths reproduce frequently. If you have any more suggestions let me know.  Thank you for your time. Travis Hunt addicted reefer. <at this point... stable water quality is key. I strongly suspect that there is no pathogenic or parasitic concern here. Anthony>

Parasitic snails stuck to Marine Turbo 12/3/03 I've attached a photo of one of my snails against the Plexiglas.  A couple of these snails ( Turbo ? ) have tiny shells attached to their shells.  Could these be yet another type of snail living on my snail.   <Argh... these are parasitic snails preying on your larger Gastropods> I doubt that these snails have enough maternal instinct to carry there young around.  I am so confused. <they are clearly parasitic to me. Manually remove the small snails when you see them with tweezers. They will wane in time> Thanks,  Edward.
<best regards, Anthony>

Coris wrasse on Pyramidellid snails hey, thanks for answering my question.  By the way, I have another question.. I hope you will answer it to. How good is Coris gaimard in eating Pyramidellid snails? Do you know its rate of feeding? per minute or per hour? if you don't know, I hope you can give me an approximate. I'm just curious. Thanks to all of you! more power! God Bless! <raf> < again cories wrasse not your best choice for removing the snail. cories wrasse may eat them  but not for sure. Better off with Sixline or fourline Later MikeH>

- Gastropod Problems - Mr. Fenner, I am experiencing serious problems on my way to completing my 400G reef tank. This is not my first but will be my last project as far as aquaria. My main symptom to the problem is that I can keep any gastropod alive, these include 2 Queen conch, Astrea, Margarita and bumblebee snails (usually die within hours of introduction. Physical failure appears to occur during acclimation while slowly mixing tank water with shipping water. They just start to freeze). What does survive and thrive are my fish, P. Asfur, Queen Angel, Blueface Angel (in 50 gallon refugium, even 400 gallon wont hold 3 large Angels. He will eventually find his way to my 150 gallon that is being slowly transferred to the 400.), Potter's Angel, Clown Tang, Vlamingi Tang, True percula pr, Nigripes Clown pair, small shoal of green Chromis', and a small shoal of Highfin cardinals, 3 scarlet shrimp, many hermit crabs, microfauna including Featherdusters, a toadstool leather frag (from 150 gal), a brain coral (from 150 gal), and a newly introduced Maxima (life expectancy undetermined). Hardware include PS (EuroReef) UV, Calcium Reactor, DSB over a plenum in a 50 gallon sump, 2x250 10K Ushio, 4 x175 12K. I also use regular Kent Mag, Iodine and strontium supplements. I must confess the following. I started the tank with freshwater straight from the tap 9 weeks ago, but use RO for top off and changes. Uncured live rock was cured in the display tank... needless to say this wasn't a pleasant experience for the eyes and the nose especially in the living room. A knock-off brand salt called "Nautilus" was initially mixed but I now have switched to Tropic Marin (only one water change in). The salesman assured me it was "just like Instant Ocean." Other deviations from my past include using Rubbermaid tubs for both sump and refugium, and some "Black/Moon" sand for aesthetics. Also used white and clear silicon from home depot to help seal pvc piping (but have used successfully in the past.) I have run a PolyFilter and have seen no tell tale signs for chemical toxins... the filter changes from white to beige to brown. PH seems normal 8.2 to 8.4. Temperature 80. Eventually I hope to complete the tank with SPS, but will remain patient along the way. What toxic conditions might I have with this tank? Even the dreaded C. retrogemma introduced from the live rock transferred from my 150 gallon tank cant survive. I do believe I may still have some small ammonium levels, but nothing the PolyFilter has detected. What gives? What should I do? Sincerely, DD <Well... a couple of things come to mind. First, as much as I like PolyFilters, I wouldn't rely on them as indicators for the presence of nitrogenous wastes. If you think you have ammonia or nitrites, use a test kit - be certain. Next, I'm not at all familiar with Nautilus brand salt but have used Tropic Marin for many years without issue. While I have no real proof, I'd be willing to lean in the direction of the salt as the source of your gastropod problems, although there is another possibility that I'll touch on in a sec. It's actually not that easy to produce salt, and many of the lesser players have problems with consistency from batch to batch. You've done the wise thing by going to one of the brands that is well known for its consistency, Instant Ocean would be my second choice. It's going to take many water changes to get the Tropic Marin in as the primary salt in your tank, and I wouldn't do this via any large changes so take your time. You should be able to try again in a couple of months. So... there is also the possibility that the source of these gastropods is suspect - perhaps they don't acclimate well there, perhaps they have a bad supply - there are a couple of possibilities here, but it's really hard to be 100% conclusive about what the problem might be. As I mentioned, try again after you've got all the salt swapped out and see how it goes from there. Cheers, J -- >

Crop Circles on Turbos? >I picked up 4 large turbo snails and I noticed that they had 20 - 40 small white circles on their back.  Whenever they rub up against any of the live rock, they leave behind some of these "things".  I called the pet store and they stated that they could either be eggs or worms - but whatever it was would not affect the rest of my tank.  Can you give me any more information that that.  They are not on the snail, only the shell, and all 4 snails seem very active.  I'd appreciate any input you can give me.  I just found your site about 2 weeks and can't believe how much information is on here, but didn't seem to find anything regarding these egg/worms spots.  Thanks much,  Liz >>I wish I could tell you something definitive about these mysterious circles, Liz, but I can't.  My own first guess would be that if the snails appear to be rubbing their shells on purpose they might be depositing young, but I don't think they're eggs.  I rather bad thought is some sort of odd parasitic infection, parasites are known to make animals behave in some truly bizarre ways, but again, I would be speaking from a position of complete ignorance.  I suggest posting on our forums http://www.wetwebfotos.com/talk or on reefs.org forums.  There seem to be quite a few folks who have this snail-breeding thing down, and they may have better information than I.  Marina

Possible Coralline Orange Lethal Disease? 3/7/03 Greetings crew, <Howdy> I have an Astraea snail who's purple coralline turned bright orange within 24 hours and is now fading to white. <a simple bleaching event. This snail was either caught out of water during some water exchange/drain event, or the water quality (Ca/ALK levels) in the tank have degraded and stressed the corallines> I have not been able to find much info on C.L.O.D. but Am afraid that's what it might be. <rest assured, this is a simple bleaching event. CLOD is rare in the wild, let alone the hobby. See a little bit of info here: http://www.geology.iupui.edu/classes/g130/reefs/IWO_174.htm excerpted: "Reef building algae and coral reef ecology have re-cently been found under attack by a previously unknown disease. Coralline lethal orange disease, known as CLOD, is caused by a bright orange bacterial pathogen that is lethal to the encrusting red algae (corallines) that deposit calcium carbonate on the reefs. These algae cement to-gether sand, dead algae, and other debris to form a hard, stable substrate. CLOD was initially found in 1993 in the Cook Islands and Fiji; by 1994 it had spread to the Solomon Islands and New Guinea; by 1995 it was found over a 6000 km (3600 mi) range of the South Pacific. No one knows whether it has been recently introduced from some obscure location or whether it has been present on the reefs but has now evolved into a more virulent form." Would it be a good idea to remove this snail just to be safe? <not necessary... the problem is not likely the snail at all. Do check your calcium and alkalinity levels... likely one has strayed low. Else, a recent sudden influx of fresh evaporation water near the snail could have stressed the corallines. Still the most common cause is a water change when you leave the reef lights on (bad! for corallines) which bleaches them with the sudden increase in light without the diffusion of water. The snail was perhaps high on the glass unnoticed> Thanks Emerson <best regards, Anthony>

Snail shell shedding >I have a large turbo snail that I noticed this morning had somehow shed its shell but is still feeding. although looking very bizarre it seems fine. why is this? >>So, you're saying that it's basically now a naked snail?  I have *never* seen this...it's not like they go and pick up a new one. >I have a 55 gallon tank with live rock 15 hermits 2 sand-sifting starfish a white spot sea urchin 10 mixed snails some soft coral and mushy rock and an algae blenny. >>Have any of the hermits taken over the Turbo's shell?  What do you mean by "mushy rock"?  Is it a sponge?  I don't think it has *anything* to do with the snail losing its shell, though.  How odd. >Temp is 80 degrees, Ca s 400-429, ph is 8.2-8.4.  thanks, Adam England >>Well, Adam, you've gone and stumped me here.  I've seen Turbos lose their shells, but either something TOOK it, or they're sick and ready to die (if not dead already).  Marina

Sudden Nerites Death Syndrome - 4/15/03 Hello WWM crew. <(2010 HAL voice) Good morning Dave. Ha! I always wanted to say that! Just like HAL......Gosh, I am a nerd. Anyway, I'll just say my name is Bob Fenner.....not Paul Mansur Hehehheeee> Before I go any further, I'd like to thank you for the excellent job you guys do....this website has proven to be an invaluable resource for me. <Glad to hear it. That is why we do what we do. Thank you for validating us>  Now onto my question.  I have a couple of Nerites snails, and they appear to be dying slowly, and I'm completely stumped on this one.  I also have a couple keyhole limpets and a bumblebee snail (which are doing fine, I might add), so I really am quite unsure of what could be causing this.  My tank param.s are as follows-am-0, nitrite-0, nitrate-<10ppm, KH-9, CA-380. <Calcium and KH are a little low. Not enough to kill them though. Sounds like they could be starving or already sick. Do you quarantine?> As soon as I put them in the tank, they choose a spot on the wall of the tank and stay there, never moving at all, and eventually die.  Absence of food is no issue, as there are small amounts of filamentous algae for them to graze on, <Hmmmmmm> so I really see no reason for this. <Nor do I if food is not the most obvious issue here. Not totally sure though>  Is there something that Nerites, and snails in general, are sensitive to? <Well, pretty much the same things that other snails, limpets and many invertebrates would be sensitive to. Hard to say what the problem is here but the limpet and the other snails would tip you off if something were severely chemically wrong.> I know they are intolerant of high nitrate levels, <To a degree> but that is about all I know when it comes to these tank janitors. <Well, food issues aside (try adding Nori), medications, chemicals, various predatory animals, parasitic disease, or just plain highly stressed animals are killers.> Hmmmm.... If you could provide any insight here I would really appreciate it!  Oh, btw, the only additions to the tank as far as supplements are concerned are Kent essential elements and C-balance. <Well. insight.... hmmmm.....could be any number of the above I mentioned. Too hard to tell. How long has the tank been set up? I have had some Nerites live for a short time in the beginning months of my setup, but now almost two years later I have had three Nerites in my tank for 5 months no problems. Try adding a sheet of Nori or some type of sheet algae and see what that does, but nothing stands out really. So many possibilities. One piece of insight might be to steer clear of Nerites and try some other algae cleaner like an Astrea, Trochus, margarita. That is about all I can come up with. So sorry for the lack of a definitive answer. Try the various reef site forums as well. Many knowledgeable snail keepers out there> Thanks again, and kudos on the AWESOME website. <Thank you very much. Paul> -Dave Conners

Snails Dying Hi Bob, <Steven Pro this morning.> I have a 75 gallon reef with 20 gallon sump. Water quality is good (as indicated by coral appearance) <While watching your corals is necessary, it does not take the place of consistent monitoring with test kits of the major parameters.> but I have a chronic problem. My snails keep dying. Not all at once write after introduction as you would expect from improper acclimation, but one-by-one over a period of months. <Starvation or predation> The snails I use are the Cerith, Nerites, and Turbos. The Turbos seem to last the longest. Since I have Fiji live rock, my fear is that there is a nocturnal snail predator in the tank that I have not been able find, trap, and removed. There are two rather large brittle stars and a unidentified crab <The crab is a likely suspect.> that stay well protected in the live rock. The brittle stars I think are safe but not sure about the crab. So far no signs of grazing on the corals as you might expect from a crab. <Crabs are opportunistic omnivores (they eat anything they come upon).> In addition, there is some sort of creature that appears at night that I have never fully seen. What I do see of it reminds me of an elephant's trunk that is sticking out of the live rock sifting the substrate for food. <Some sort of worm> Kudos if you can ID this one for me. <I would check out Dr. Ron Shimek's website for his key to animal ID. You can find his site on our links page or by searching the net.> This creature is very sensitive to light. Very cool, but still a candidate for a pest. There does seem to be an unusual amount of trash around where this guy lives. Oh yes, one more thing I have a bunch of small nocturnal white snails with brown strips that came with the live rock, any idea what these are. Please let me know what you think. I guess a disease is also a possibility. Thanks in advance. John L. Allen <Best of luck to you. -Steven Pro>

Snail Problems Mr. Bob and friends, <Howdy> If I may, a few questions relating to snails (of the turbo variety...I think). I recently invested into the little critters to help clean up my tank. About a month ago I purchased three (one died day after) and then two weeks ago purchased two more (one died day after). And it looks like this morning the 3 remaining died. A few things about the tank. My heater busted about a month ago.  <no biggie> After discussions with your team, decided to go with the Ebo Jager 200 watt, (because I'm looking to upgrade from a 30 ga to 55 ga). I chatted with a customer service rep (not FFExpress) and was assured the 15" of the 200w was the whole heater and it would fit in my 30 ga. Well currently the 200w is on it's way back to FFExpress and a 100w heater is on it's way to me. Without the heater the tank maintains a steady temp of 68 to 70 degrees, Also last week I added a bio wheel to the tank. The water cleaned up nicely but wondering if the introduction of carbon into the tank might have affected the snails.  <Not likely... would only help> And regarding my local pet store. Some of their tanks are listed in Bob's book as one's to avoid. I didn't have much luck with a few fish I purchased there, but it's the only local store where I can purchase snails and live rock. (since the other store closed). The snails did a great job while they were in the tank and looking to add more, but plan on waiting until the heater arrives, and possible purchasing from FFExpress. Any thoughts on how to better maintain the little critters or what else might of affected them would be greatly appreciated. (all levels are fine and the fish are very active and colorful) Thank you kindly, Dave <some off brand salts have been accused of being hostile to inverts (snails and echinoderms in particular)... any chance that your "Crystal" salt was not Instant Ocean, Tropic Marin or the like? Else, consider putting a Polyfilter in the system to sop up a potential contaminant. Heavy metals are a problem>

Re: snail problems Mr. Fenner and friends, <cheers> Not sure who to thank for getting back to me. Seems the snails were playing dead?  <osmotic shock> They didn't move for two days (all three). And the morning in question when I checked them, they each had their doors closed and were detached from live rock and glass. (Which lead to the conclusion that I lost all of them.) Of course later in the day after emailing you, I noticed one had moved. Then over the weekend each one had moved slightly, and they started eating again this morning. I think it's connected to the temperature?  <unlikely unless there is a big diff from dealers tank to yours... even still, no problem unless your acclimation was abrupt> The only salt that I've ever used is reef crystals, same category as instant ocean and tropic Marin as you suggested?? <a fine sea salt> thanks for all your help, Dave <best regards, Anthony>

Snails Hi guys. I have a question concerning my snails. They can't seem to stay attached to my rock or glass. I have 8 snails and about 3 every day are on their backs on the bottom of tank, and have to be turned over. I have 3 Astreas, which I know these are prone to falling off and can't right themselves, and I have 5 margarita snails. They just keep falling off whatever they are on, what could be the cause of this?  <quite strange... but not likely a snail or water quality issue. More commonly it is a fishy imp or wannabe predator. Hawkfish and wrasses are notorious for knocking snails off the glass. Do consider the fishes in your tank> Getting tired of having to reach into tank and put them back on the rocks. Also I was going to get some phytoplankton for my corals, which brand would you recommend between Kent Marine and Dt's, or are they both good enough?  <reports have shown DTs to be one of the very best. Still... are you willing to whack it in an electric blender for every feeding? And do you even need phyto (gorgonians and Nephtheids). Most popular coral feed on zooplankton... not phyto. Best regards, Anthony> Thanks for help.

Mysterious disappearance of snails and other algae eaters Note* if the accomplished aquarist reading this is the same that answers FFExpress questions, you can disregard this as I have sent the same question there. I wanted a few opinions so I sent it to both. The tank that I keep in my dad's oral surgery office is a great success, relaxing patients and staff alike. However, lately it seems that hair algae is the main feature of the tank. I have read for many hours on WWM and FFExpress, which, by the way, provide priceless literature, but have yet to find a solution. Here is what I wrote to FFExpress: I have been fighting a hair algae problem for quite some time (a year) in my 45g reef tank. The only fish are a coral beauty angle and two damsels, sharing the tank with a cleaner shrimp and some soft corals. Nitrates are about 4 and dropping, phosphates 0, pH 8.1, calcium 450. The nitrates have steadily dropped since I upgraded to a remora pro protein skimmer. Lights are a 65w SmartLight and a 20w actinic. Temp runs from 79 to 82 depending on the time of day. <<A quick aside here... do try to keep that more consistent, even if it means bumping up the heater to keep the temperature from swinging back and forth - a steady 82 is better than a three degree swing.>> I have tried adding snails, hermit crabs, emerald crabs, a sea urchin, and a lawnmower blenny to eat the algae, but all of them died within about a month. I would assume that at night, low oxygen levels around the large quantities of hair algae suffocate them - all of the other fish and corals are thriving and besides these bottom feeders, a fish or coral has never died in my tank. <<If the problem were truly low oxygen content in the water, you wouldn't have such selective deaths.>> I read once that SmartLight (half and half actinic and daylight) bulbs sacrifice quality of light output and often promote algae. Have you heard anything of this nature? <<No, but I would say that algae is a very successful life form and needs no special lighting one way or another to thrive. I think you might want to look into phosphate levels in this system - nutrients that would help promote the growth of algae.>> Would the high temperatures (max 84) be killing the snails or is it just lack of oxygen at night? (And yes, high temperature means even lower oxygen levels) <<That is true, but no, I don't think that is what is killing the snails.>> I have set up traps to see if there is a predator that could be eating my bottom feeders, but I found nothing. <<Doesn't mean you don't have one... but again, even if you had the dreaded mantis shrimp in your system, it wouldn't be at all selective about what it ate. Food is food.>> I scrubbed all the live rock when I added the Remora but the algae has all grown back. <<Oh... so you do have a skimmer - this would eliminate the potential for low oxygen as they return a good deal of oxygen to the system.>> Would changing my lighting and/or adding a thermoelectric chiller help? <<I don't think so, but you could reduce the amount of time the lights are on - I assume they're on eight hours?>> Any other suggestions? <<Continued manual removal.>> I have already minimized feeding, used PolyFilters, and tried a 24 hour lit algae refugium. Nothing seems to help. Thanks for your suggestions, any insight would be greatly appreciated. <<Well algae problems are not at all uncommon, and typically due to husbandry issues. I'm not sure the temperature has anything to do with it. If you did at one time overfeed, then it will take some time to gain the upper hand. You may have to clean the rock frequently to get ahead of the algae, but you might also want to consider increasing the circulation in the tank to make it more difficult for the algae to settle down in the first place.>> Thanks again. <<Cheers, J -- >>

Disappearing Fighting Conch Dear Bob, <Steven Pro in this morning.> I set up a 30 gallon reef tank in April and, after cycling, added a fighting conch along with some other snails in May. Everything was fine, the conch was active and feeding all day long. I went on vacation in August and it had disappeared. I read that fighting conch will often disappear for weeks at a time, so I didn't worry too much. By the way, the other snails, corals and everything else are doing great. After 2 months, I figured it was not going to reappear and bought another one (from a reputable dealer). This one hardly moves at all and I am very concerned about it. <Kind of strange. All snails (and other invertebrates) are very sensitive to salinity shock (rapid changes in salinity). They need to be drip acclimated.> Prior to going on vacation, I also had a very large pod population and when I got back, they, too had disappeared. I figured this was just a natural cycle and that they would be back. They haven't. I don't know if these events are related, and if so what the cause might be. Can you offer any advice? <I would guess that both disappearances are linked to a lack of food. Perhaps they reproduced and grew and ate themselves to starvation. There are many episodes of these kinds of population explosions and crashes.> Thanks, Ed <You are welcome. -Steven Pro>

29G FO Husbandry Season's greetings to all of the WetWebMedia Crew!!! <And thou> Ok, thanks to all of your support I am now on the path that will hopefully bring health and happiness to all of my marine "guests".  I would be grateful for clarification on a couple of questions: (1)  Santa is bringing an Eheim ECCO 2233 (rated for 60G) and a CPR BakPak skimmer for the 29G tank.  Would live rock find enough "food" to remain alive with the implementation of the Eheim and the skimmer?  Would 30lbs still be a reasonable amount? <Yes, and yes> (2)  "Help, my snails have fallen and can't get up!!!"  What's the deal with my turbo snails, are they handicapped?  I keep finding them upside down.  If I don't upright them will they be able to right themselves?  How long can they survive "upside down" before they expire? <Please see WetWebMedia.com re "Marine Snail FAQs"... a few possibilities here. Likely alkalinity anomaly> (3)  Cleaner shrimp and damsels have not developed the relationship I had hoped.  One of the damsels began to show an interest in the scarlet cleaner shrimp.... unfortunately I have discovered it is not the "cleaning" that he is interested in.  The damsel periodically tries to kick the shrimps butt.  Charging, nipping, even swam under his tail and tried to up-end the shrimp one time.  Is my shrimp in danger?  Oh why oh why couldn't I find all you helpful people before the LFS told me to put damsels in my tank? <Give them more time together. Purposely feed the shrimp with a "feeding stick" in a corner, on a daily routine> Thanks for any advice you can share. <Be chatting, Bob Fenner>

Snail health, shrimp nutrition Mr. Fenner thank you for the quick response.  Regarding the questions below: (2) "Help, my snails have fallen and can't get up!!!"  (a) I noticed many references in the "Marine Snail FAQs" to two products (i) B Ionic and (ii) Sea Balance.  I have not been able to locate these products (although I did find Kent Marine products at DrsFostersSmith.com).  Can you point me in the right direction? <These calcium and carbonate products are sold by many e-tailers and retailers. If interested in them you might try the folks listed on the Marine Links page: http://www.wetwebmedia.com/marlinks.htm>   (b) I also noticed that you recommend 4 watts of appropriate lighting.  I only have 22 watts of "cool white" on a 29G.  Is the lighting contributing to the snails issues? <Not directly> (3) Cleaner shrimp and damsels have not developed the relationship I had hoped. (a)  What exactly is a "feeding stick"? <A store bought or DIY device (a wood or plastic dowel, length of rigid tubing) for delivering food down to the animals> (b) the scarlet cleaner has been in the tank 5 weeks and has never been target fed.  How can I tell if he is properly nourished and healthy? <If it's out and about, looking like it's trying to eat (other organisms) it is likely hungry> Thank you <You're welcome. Bob Fenner> Rex.merrill

Invert problems... Poisoned Starfish & Snails? I have a 300g system set up as follows: natural seawater,55g sump with chiller, skimmers, return pumps,55g refugium with red mangroves, Caulerpa, sea lettuce, various algae. I have 3 175w 5500k halides supplemented with VHO actinics that are all vented. I have tested nitrites, nitrates, ph, calcium, magnesium, iodide, iodine, strontium, and my alkalinity. The water fluctuates between 77 to 78 degrees Fahrenheit. Now here's the problem, just in the past day I noticed that all my brittle stars and my nudibranchs have become immobile. They are not dead just stopped moving. Everything else fish and inverts are fine. All the hermits, Cukes, other starfish, and all fish are fine and show no signs of any kind of duress or any other types of abnormal behavior. This is the first time I have ever had this happen and was just wondering if anyone else has or might have any suggestions. PS=Tank has been up for bout year and half all was fine till yesterday. Thanks Bill Huggins <the symptom of sudden starfish immobility is actually rather common (snails too... have you checked your shelled snails? Turbo and Astraea species and the like). It almost always coincides a large water change and often with a new sea salt. Sometimes the change, increase or addition of a new supplement does the same (Magnesium and other metals rank high for OD potential). Osmotic shock is also a candidate... as with adding a large amount of freshwater after a period of slight neglect of evap top off. I'm also somewhat disturbed about you comment "all my nudibranchs"?! I really hope that you've misused this term and mean some other shelled snails. The are very few nudibranchs that can realistically and responsibly be kept in captivity. Most of the "bad guys" will starve to death in a matter of months (and many are toxic by the way... hmmmm?). The few suitable species graze nuisance algae (Derbesia, Bryopsis, etc) and unless you have a hair algae farm in your tank... they will die too. Please tell me that you didn't mean to say "Nudibranch", my friend... or we may have another dimension to your tanks ailment. Else, do consider new sea salt, large water change and salinity shock. Best regards, Anthony

Snails unable to right themselves Hello-- Thank you so much for all these faq's (my marine creatures would thank you, too, if they could). I have a 90 gallon tank to which I added 20 margarita snails and 20 blue-legged hermits 5 days ago. I have no fish or other creatures, besides whatever is in/on 70 lbs. of live rock, because the tank is only a month old. My ammonia and nitrite levels are 0, pH 8.4, and nitrates are <.5.  My concern is that the snails seem unable to right themselves. They will fall off of the glass or live rock, or simply end up on their backs somehow, and then are unable to turn themselves over. The first few nights I would just leave an upside-down snail as is to see if he could help himself, but I found they don't seem able to turn themselves over. Is this normal? <It is a common problem with Astraea snails. I have never heard of it with Margarita snails, but they could be the same.> Is something wrong? <Not likely> I don't see how a creature could survive very long (in the wild or even in my tank) if it stays stuck upside down, as even the blue-legged hermits seem willing to attack the snails in this position. <My understanding is that Astraea snails are collected in areas with no sand, just rock everywhere.> I would like to add my first fish on 3 days (2 false Perculas), and am hoping that I am not doing something terribly wrong. In addition, I have about 4" of substrate, much of it crushed coral containing some hermit sized shells. <Please do search on www.WetWebMedia.com regarding the use of thick layers of crushed coral. This can be problematic for you in the long run.> Is this enough, or should I find more shells for the hermits? <I would add about 20 or so alternate shells for the hermits.> And could you tell me where I can purchase marine hermit shells as I have been unable to find them. <I would check with your LFS. Eventually they will get in a bad shipment of snails and have plenty of extra shells.> Thanks for your help! --Laura <You are welcome. -Steven Pro>

Quarantine for snail? Hey Gang, I have an interesting situation. A couple of days ago I found one of my Astrea snails lying on its back.  I found it right away in the morning so it must have fallen overnight.  It appears to have been damaged in some way, I suspect my blue legged hermits, but other occupants are flame angel, golden damsels (2), green Chromis (2), and cleaner shrimp (1, L. amboinensis).  I placed it on the substrate right next to the front wall of the tank.  For a day and a half it barely moved, and eventually did start moving up the glass.  I could definitely see then that it's foot was missing a chunk near the front, and I fear that it may be missing an eye, a feeler, and possibly even mouth parts, but I couldn't see all that well and it could have just had them pulled in.  The next morning I found it upside down on the substrate again.  It is not moving as fast this time.  I want to remove it from my tank so that if it dies it won't pollute my tank, but I don't know if there will be enough food in my quarantine tank for it to survive.  What would I feed a snail that's in quarantine?  I've always relied on them to help control algae so I never fed anything to them specifically.  I would prefer to get it into a qt if there is something that I will be able to feed it. Is this something that a snail can recover from? Thanks for your help -Luke <Hey Luke, you should be able to feed him on Spirulina pellets or Nori.  There is a good chance that he will recover.  Good luck -Gage>

Healing At A Snail's Pace? Hey Gang, <Hi There! Scott F. here tonight> I have an interesting situation. A couple of days ago I found one of my Astrea snails lying on its back.  I found it right away in the morning so it must have fallen overnight.  It appears to have been damaged in some way, I suspect my blue legged hermits, but other occupants are flame angel, golden damsels (2), green Chromis (2), and cleaner shrimp (1, L. amboinensis).  I placed it on the substrate right next to the front wall of the tank.  For a day and a half it barely moved, and eventually did start moving up the glass.  I could definitely see then that it's foot was missing a chunk near the front, and I fear that it may be missing an eye, a feeler, and possibly even mouth parts, but I couldn't see all that well and it could have just had them pulled in.  The next morning I found it upside down on the substrate again.  It is not moving as fast this time. I want to remove it from my tank so that if it dies it won't pollute my tank, but I don't know if there will be enough food in my quarantine tank for it to survive.  What would I feed a snail that's in quarantine? <Well, since you're not using the tank as a true "quarantine" set up right now, I'd throw some live rock in there for the snail to graze on.> I've always relied on them to help control algae so I never fed anything to them specifically.  I would prefer to get it into a qt if there is something that I will be able to feed it. Is this something that a snail can recover from? Thanks for your help Luke <I'll tell ya, Luke- I've never ceased to be amazed at the re-generative properties of many marine animals. There is no guarantee here-but, if you have the space, and the inclination-it's worth a shot! Good luck! Regards, Scott F>

Snails and Crabs die! Dear Bob: I'm forwarding this question to you, hoping you can help out this army guy! Howard. <Okay. Oh, see Steve answered. Bob F.> <Steven Pro this afternoon. I have a few suggestions. Yes, there are commercially available copper test kits, but your fish would be affected to high levels of copper too. Any detectable level of nitrite is bad and needs to be addressed. I would also look at his acclimation procedure. Many people kill a lot of inverts by exposing them to large shifts in salinity. Float the bag for 10 minutes, add one cup of water, float for 10 minutes, add one cup of water, etc. until temperature and salinity match. -Steven Pro>

Snails (marine, health) Hello: I have a 30 gallon reef tank, 3 months old, with RUGF, Fluval 204, and a Remora skimmer, and 96w CF 50/50. The tank is occupied by 25 lbs. live rock, 2 Percula clowns, a Cardinalfish, scooter blenny, horseshoe crab, and 5 Turbo snails, as well as 3 smallish bubble-tip anemones (came with live rock and thriving), some mushroom corals, yellow and red polyps, leather coral, and a frogspawn. <A lot of life for such a small volume for sure> Everything is well, water parameters are constantly 1.023 SG, 76 degrees, 8.3 pH, <2.5 ppm NO3, < 0.4 PO4, no NH3 or NO2, and I change 5 gallons every 2 weeks. Additives include Kent dKH, liquid Ca, Tech I, and CoralVite. All of my creatures seem happy but for one strange thing. Two of my snails seem to temporarily "lose their grip." This has happened to them separately on 3 occasions. When it does, I find them upside down on the substrate, squirming around, unable to grab onto glass or rock. I have righted them before, and they seem to fall over again soon thereafter. The last time it happened, I just left the snail alone and by the next day he was crawling around normally again. Is this a sign of a problem, or is it normal? <Does sound like a problem. You mention adding alkalinity and biomineral supplements. I would be testing for anything/all that you amend... I strongly suspect that either hardness or calcium is badly out of whack here (your snails more so than the other life listed need both). Please read over the numerous FAQs files posted on www.WetWebMedia.com re marine water chemistry. Bob Fenner> Ed Marshall, Austin, TX

Re: Snails Thanks for the response. I should have mentioned that my Ca level is about 400-450 and alkalinity is within normal ranges (unfortunately, my alkalinity test kit only reports low, normal, and high - I am about to replace it). I have read that frogspawns are an excellent water quality indicator, and this coral seems extremely happy. <Depends on what is being "tested", but in general, yes.> My coralline algae is spreading on the glass and lift tubes as well. Unfortunately, my initial research into the hobby did not convince me that 30 gallons was too small. I am now convinced otherwise, and I am planning a 75 gallon setup that I will move everything to within a few months. Is it OK to cycle the new tank with substrate/biomedia from the old one and move everything at once, or should I move things gradually? <Should be fine to make the switch all in one go> If so, should I move corals and live rock first? Or fish? <Move the gravel, LR, old water first... next the livestock...> By the way, I asked at my LFS and they said the snail thing is normal! <Bizarre... what is "normal" about the snails falling off onto their backs? Does this make sense? I mean, what sort of survival value might this behavior represent?> Thanks again for your time and wisdom - Ed Marshall <And you for your involvement, sharing. Bob Fenner>

Snails (marine, loss, HP04) Hello: I have a 30 gallon reef tank, 3 months old, with RUGF, Fluval 204, and a Remora skimmer, and 96w CF 50/50. The tank is occupied by 25 lbs. live rock, 2 Percula clowns, a Cardinalfish, scooter blenny, horseshoe crab, and 5 Turbo snails, as well as 3 smallish bubble-tip anemones (came with live rock and thriving), some mushroom corals, yellow and red polyps, leather coral, and a frogspawn.  <A lot of life for such a small volume for sure> Everything is well, water parameters are constantly 1.023 SG, 76 degrees, 8.3 pH, <2.5 ppm NO3, < 0.4 PO4, no NH3 or NO2, and I change 5 gallons every 2 weeks. Additives include Kent dKH, liquid Ca, Tech I, and CoralVite. All of my creatures seem happy but for one strange thing. Two of my snails seem to temporarily "lose their grip." This has happened to them separately on 3 occasions. When it does, I find them upside down on the substrate, squirming around, unable to grab onto glass or rock. I have righted them before, and they seem to fall over again soon thereafter. The last time it happened, I just left the snail alone and by the next day he was crawling around normally again. Is this a sign of a problem, or is it normal? <Does sound like a problem. You mention adding alkalinity and biomineral supplements. I would be testing for anything/all that you amend... I strongly suspect that either hardness or calcium is badly out of whack here (your snails more so than the other life listed need both). Please read over the numerous FAQs files posted on www.WetWebMedia.com re marine water chemistry. Bob Fenner> Ed Marshall, Austin, TX

Do Snails Get Ick? <<JasonC here...>> well that's good , that snails and hermits don't get ich , that way I can have a bunch of them , <<what's a bunch?>> you said starfish don't' get it either right?? <<I did say that, didn't I>> you see I am wanting to save my fish and I have had people to tell me if I just leave the ich in there I can have starfish and snails and hermits, but some say it kills everything including live rock <<I think perhaps those who are telling you "it" kills live rock mean this: some of the items one might use to treat ick [copper, etc.] are pretty close to poison, and often invertebrates [snails, Seastars, etc.] suffer 100% mortality when you pour this in your tank. If will kill the stuff that makes live rock live. That being said, ick - the parasite Cryptocaryon - will NOT by itself kill live rock, but you can by trying to treat it.>> thanks for your help , do you have a messenger <<Uhh, not sure I'm hip to this "messenger". Cheers, J -- >>

Snail Quarantine? You guys are the best. Thanks so much for all your information. A couple questions... I've read conflicting info about whether or not to quarantine snails prior to adding them to a tank. We want to get about a half dozen turbo snails from our LFS who has them in established reef tanks. Is a quarantine or some sort of dip necessary before placing them in our FOWLR tank? <Ideally, yes quarantine. Also a good idea to not put outside water (from the LFS) into your tanks.> Also, how concerned should I be about the copper pipes in our house? <Minimal for most.> Will R/O remove any copper that may leach into the water? <Yes with many other things.> Thanks again. Karen  <You are welcome. -Steven Pro>

Snail Deaths II I'm sure that they are turban snails because the LFS has Astrea snails as well (look like little pyramids and much smaller if I recall). <Yes, a good description. Astrea are about dime size, Turban about quarter.> Do you think I should try another few snails or a shrimp in a few weeks and see what happens? <I would like to know what is causing your snails to die first.> Also thinking about putting a PolyFilter just to see what comes up - or do you think that it's unnecessary? <No, sounds like a good idea, my next suggestion.> I checked all water parameters again (using all new test kits (Tetra), all same except the Nitrate readings indicate 12.5 mg/L vs. ppm) this afternoon. I now have an extra set of test kits, but still no snails. Still confused. <See what the Polyfilter reveals and give us an update. -Steven Pro>

Reply about snail problems Hi guys, just replying to Anthony about a prior discussion. Anthony, it took me some time but I ran the test as you suggested. The snails in the water change water are fine, they were immediately active, while the snails in the tank did the usual fall over to the side. I also bought two red leg hermits for the test, with the results the same. I took the snails and hermits out of the tank and put them in the water test batch with a piece of live rock and they are moving about and appear fine. I have also bought a Salifert magnesium test kit. The results were 1410. This is in the range of seawater I think. Do you think it could be a contaminate or something like low oxygen saturation?  <much more likely a contaminant... not O2 level at all likely although that is easy enough to test for. Some rocks have embedded deposits in them... who knows, perhaps a piece of you "live rock" is an encrusted iron relic from a Spanish Galleon! Heehee... do use a Polyfilter or two to absorb and possibly indicate (color change) contaminants> I have a lot of water movement about twenty five times the tank volume per hour. I took off a second light which had some rust on it. Could this be the source of the problem?  <unlikely enough of a problem for hardy crabs. Any of the rock ever been through a copper treatment before?> On a side note I was going to coat the bottom edge of the light with a latex coating used for grip on tool handles, any thoughts?  <seems like a good idea once cured> Thanks for your help, Lowe <best regards, Anthony> Lowe Winfield Runkle II

Re: Snail problems Anthony, thanks for the reply. I use reef crystals salt which I think is made by IO.  <ahh...yes, a very fine salt and not the brand that I suspected as problematic> I run Polyfilter in the return flow from the skimmer as well.  <excellent, but still a stumper about the snails!> Should I add some magnesium supplement or do they make a test kit? <not necessary, my friend. Especially with regular water changes. May I suggest that you run a test with a new batch of seawater (mixed and aerated for days) with a single snail inside of it to try to determine if the problem is in the tank or with the source water. Yes... lets try to reduce some variables now. Best regards, Anthony>

White spots on snail shells I searched your site (which is wonderful!) and haven't found any information about white spots appearing on snail and hermit crab shells. Any ideas?  <likely a settled spawn of sessile snails or micro fanworms. Common and harmless... do browse here: http://www.tcnj.edu/~maughme2/faq.htm> When we got the critters, there were no spots on them. They started appearing about a week later. They are proliferating now. Some shells have three or more perfect circular white spots.  <sounds like a worm with a small calcareous tube> The tank was started almost three weeks ago with some live rock, a deep sand bed, and microorganisms (from GARF). Added the critters after one week when the rust brown algae (diatoms?) started appearing (and is now flourishing!). Water chemistry tests 0 for ammonia, nitrites, and 10ppm for nitrates. Ph is at 8, temp at 80 degrees. Added Caulerpa (sp?) last week in the refugium. Nitrates are going down slowly. You probably need more information but I'll let you ask because otherwise I could type a novel. :) Tricia <no worries... do browse the above link looking for a familiar face. Anthony>

Dead Snails I recently moved. Both houses are on wells. In the new house snails die almost instantly. Standard water tests have not revealed any insights. Other fish and inverts have done fine. Do you have any suggestions. >> Yes I do... get/use a Reverse Osmosis unit for cleaning up your source water... for fish and your own/drinking, cooking use... Could be "just" saturated gasses in the well-water, or somethings' more permanent... If I "lived there" I would have my water checked by an independent lab... to ascertain what's in it... And definitely, I would/do use an RO myself... Bob Fenner

Snails! Bob, About 1/2 of the snails I put in the tank (part of the clean-up crew) have died...that is, their shells end up empty and the little discs that cover them when they go into their shells end up on the gravel. I remove the shells...some stink and some do not. I think the crabs go after the remains of the snails. <Maybe the "befores" as well...> Anyway, this morning before the lights came on I noticed a couple of dozen small snails on the glass! I suppose the snails could have multiplied, right? Later, after the lights came on, most of them "disappeared." Of course, they have not left, but they are small enough they can blend into the rocks quite easily. <Maybe... perhaps these are others that were on your live rock...> Is it normal to have snails reproduce like this? How long before they get bigger? I am curious because I'd like to have more snails, but am reluctant to buy more if there are so many little ones about. <Depends on species... and the real net causes of the others mortality... May be a predator or two in your system...Alpheid shrimps, mantis... many possibilities... Or, a chemical "imbalance"... most likely a lack of biomineral and/or alkalinity... very common causes of loss.> John >> <And you. Bob Fenner>

Astrea snails Hi! I have recently set up a 55 gal. Marine tank with 50 lbs. Live rock. The tank is pretty much cycled and I'm getting ready to start stocking fish. About 10 days ago I added 25 Astrea snails to control the brown algae that was going crazy on the rock. The snails did an amazing job of cleaning it off. Anyways, I've noticed that many of the snails like to hang out at the water line at the top of the tank. Is this healthy/normal?  <Not necessarily unhealthy or abnormal... but there may be a low oxygen situation, some other chemical, physical factor at play here... > If not, what should I do? The water quality parameters are all perfect, pH 8.2, and I've just started adding calcium & alkalinity supplements to help out my coralline algae. Thanks for your advice, Suzanne. <Be careful on the supplements... this may be the root cause... I suggest adding these to your pre-made "water change" water container, and supplementing along with this new water. Please see the section titled "Seawater" on the www.WetWebMedia.com site for particulars about pre-mixing and storing synthetic seawater, and the numerous "Supplement" pieces and FAQs about precautions and use of these materials. Bob Fenner>

Snails My snails were excreting what looked like a milky liquid tonight--lots of them were doing it. Is this reproductive activity? <Perhaps... could also be evidence of some sort of negative reaction to a stimulus... Did you "do something" immediately before observing this phenomenon? Like adding a chemical "supplement"? Bob Fenner>

Re: Snails I did add a third powerhead in one end of the tank where it was a little "dead," which did result in some stirring-up of the substrate in that area. Possible release of ammonia/other toxins from the disrupted LS? <Perhaps... Bob Fenner>

Die-off dear bob, I wrote you several weeks ago re: snails going "dormant" when introduced to the tank. then they die of starvation. In addition, my coral, one at a time, are dying. all my water test numbers are good. you suggested adding magnesium. this has not worked. could it be possible that a bacterium has invaded the tank and is causing the damage?  <Very unlikely... much more common are chemical, physical anomalies... please do read through the "Toxic Tank FAQs" part of the Marine Index on our site: www.WetWebMedia.com for accounts of others> I also have a large growth of hair algae growing on live rock and decorative (non-live) coral. any suggestions, I am almost ready to dismantle tank and give up ( after 10 years). awaiting your response to help me. <Perhaps the best idea is to tear down the system and re-set it up... with new substrate, at least some new live rock... this is what I would do. Bob Fenner, who apologizes for late replies... am visiting in Asia.> thank you, Lowell Halpern

Cowries Bob, I have kept a cowry in a 10 gallon tank for 4 months, along with live rock and a Domino damsel, and I recently purchased a 55 gallon tank and is currently in the process of cycling. To accelerate the process I have added my live sand from the old tank to the new, and added the domino damsel as well as a velvet damsel. Both seem to be doing fine, however when I moved the cowry (Cypraea mauritiana) to the new tank, she has stayed retracted in her shell. This morning I moved her back in the old 10 gallon tank, waiting to see if she will move at all well that usually takes place at night). I have tested the water in the new tank and it was PH 8.2, Nitrite 0, Ammonia 0.25-0.50, Nitrates 0ppm(I think,...I'm new to this). <Mmm, the Cypraeids are sensitive to "new tank" conditions... the ammonia was likely harsh here... and a good idea to not lift these mollusks into the air (better to move on their rock in a bag, plastic jar...> Do you think I should have waited longer to introduce the cowry to the new tank? <Yes my friend> She usually feeds on algae (scraping rocks or the glass). Also, I haven't been able to find any info on cowries. Would you suggest a particular web page? Please advise.. Thank you, D. <Please insert the name of the family "Cypraeidae" into your search engines. Not much of "practical husbandry" on these shellfish on the net... but some. Perhaps you will write a definitive piece on their captive care. Bob Fenner>

Blue-Green Algae and Snail Deaths I have read through your site and found a lot of helpful information. I have also looked through FFExpress for info but my problem is still persistent. I have tried large 20% water changes, I even tried 50% once and killed a starfish. I use R/O water a 24GPD Kent Marine TFC to fill the tank, for top off, and water changes. Let me describe my tank: 90 Gallon 10 Gallon Sump rated for a 125, Balls removed CAP 2200 Return Pump 50 Pounds Rubble Manano Rock 50 Pounds Fiji Walt Smith 50 Pounds Mixed Course/Fine Atlantic Crushed Shell Aqua-C In Sump Skimmer Rio 1700 for Skimmer Rio 1100 In Tank for Movement 2 Air Stones for movement 6 4' Fluorescent Tubes 2 Actinic, 1 50/50, 3 20,000 Lux - 13 Hour Timer 0 Ammonia, 0 Nitrite, 0 Nitrate, 0.5 or less Phosphate, <I'd shoot for zero percent...> 350+ Calcium, 8.4 Ph 78 degrees F The tank has been up for 5 months Kalkwasser,  <Drop the Kalkwasser habit, and get on to using two part supplements here> Strontium, Iodine added every 3 days 1 Yellow Tang, 1 Huma Huma, 1 Green Chromis, 1 Striped Damsel, 2 False Percula 2 Green Brittle Star, 1 Chocolate Chip Star, 1 Cleaner Shrimp, 4 Green or Mithrax Crabs, 3 Snails down from 12 I know I need additional movement and I am going to add 1-3 move Rio powerheads 1100-2500? My big question is when I do a weekly water change I remove 80%+ of the algae with gravel backing but a day or so later it is back and still as unattractive as before. I have been hoping the tank would grow out of this ugly stage soon as my other previous tank had but it only had a diatom problem due to my overfeeding.( Porcupine Puffers are so cute and always hungry, I could not resist) The Holidays are fast approaching and I have the honor ( or at least the largest house ) of hosting Thanksgiving. I would like to solve this problem by then. <You need to undertake a few approaches here, maybe chemical filtrants, in addition to enhanced circulation, competition by macro-algae...> As a backup plan I was going to do a water change that morning. This tank is my pride and joy and I want it to look as good as I know it can. After a water change when the tank settles it is truly a live piece of art. I care nearly as deeply for my pets as do I care for my family. Please offer any advice you can.  <My advice on algae control is posted on our site, www.WetWebMedia.com, have you read the sections on it there?> I also have been losing Turbo Snails, I suspect the Chocolate Star. I have watched him crawl over an overturned snail before it can right itself and sit there for hours, not moving. The trigger has also picked at the lest than healthy ones. If you can offer any advice I would greatly appreciate it. <Read my friend. Bob Fenner> Sincerely, Joseph M Howell

Dying snails Hello Bob, I wrote to you not so long ago. You were a great help to me! I wonder if you could help me again. Two days ago I was inspired by a post I read on your daily Q&A and decided to rearrange my LR. I did so and it looks wonderful. I changed the water yesterday and though my corals showed some stress they are back to their original glory. <Ah good> My problem is that I have found three snails dead today. I checked my water Ammonia & Nitrite 0, Nitrate 5ppm, Alk 2.8milq, Ca 425, those are my normal tests. My skimmer is bringing out more then normal but I thought that was because of the mess I made. <Yes... and the transient chemical changes likely the cause/demise of the snails> Do you have an idea of how I can find out why my snails are dying? I pulled them out as quickly as I could. Would it be a good idea for now to run some activated carbon?  <Yes, a good idea> I'm not sure what else to do. I though maybe because I rearranged the LR added some dead rock (cycled & cleaned well) 10lbs, and 20lbs of new LS I messed up the food chain. Thank you for your time! Libby <Not likely a long term challenge. Your system is likely re-stabilized now, but I would run the carbon. Be chatting. Bob Fenner>

Aquarium question (marine snail behavior) Hi, thank you for your time. I was just wondering why my snails seem to spend all their time at the top of the tank. Is this normal or is this some indication of poor water quality? <Could be part of a given species, populations natural behavior (many are amphibious) or could be "water quality" as in low oxygen... even "low food"... or even just adventitious behavior... a quality of living things.> They are turbo snails in a new (2 months old) 45 gallon reef tank. Thanks. <Oh... maybe lack of oxygen, food, water quality. Bob Fenner>

Snail problems Good afternoon guys, I am having a problem keeping snails in my tank. First the stats; at last test yesterday, temp 80, salinity 1.024, ph 8.4, zero amm., nitrates and phosphates, calc at 400, Alk at 5.5meq/l. It is a 37 gallon with a Remora skimmer, CPR hang on refugium and about sixty pounds of live rock.  <all sounds very fine> I have only a Banggai cardinal in it right now. Last time I thought maybe I didn't acclimate them properly, so this time I took four hours adding a couple of tablespoons of water every ten minutes.  <wow... impressive!> They were active in the bag then when I put them in they go completely inactive leaving their foot outside the shell and not moving at all. Is there something I am not testing for that could be the cause?  <notorious magnesium sensitivity... what brand of salt do you use. I have heard many aquarists complain anecdotally for years about a certain company that has changed their name a couple of times. If not using a mainstream brand like Instant Ocean, do consider> I have purchased snails from a variety of sources to no avail. As far as supplements, I add two part calcium, essential elements and Iodine all from Kent. Any help would be greatly appreciated as I am growing more discouraged. As always thanks, Lowe <do consider a Poly Filter with consideration for the possibility of another metal contamination... indeed a common snail. starfish killer. Best regards, Anthony>

Snail Deaths Dear Mr. Fenner, <Steven Pro in this morning.> I have a problem that I can't figure out so I thought I'd consult your expert advice. My problem is that my turbo snails die within a month of introduction. Tank is a 75 gal. approx a year old. Overflow to a TF1000 in a 20 gal sump. 299 watts pc lighting ( 2 full/1 blue), 90 lbs of LR, 1 inch of arg. sand, 2 Rio powerheads for circulation. Temp: 78-79 Salinity: 1.023 PH: 8.4 Nitrite:0 Amon:0 Nitrate: 20ppm CA: 350 (trying to get it up w/Kent 2 part solution) ALK: 7meq/L <Calcium and alkalinity are a both a little low. It is going to be expensive to raise and maintain both using two-part solutions. You should investigate the use of calcium reactors and Kalkwasser on the www.WetWebMedia.com page. Not related to your problem with snails, however.> Copper: 0 Phosphate: ? (buying this weekend, but I assume low b/c I use RO water). Activated Carbon in sump. Weekly 8 gal water changes with aerated (24 hours) RO water (Not RO, DI) and Instant Ocean mix, heated to tank temp - but can't get the ph to same level as tank, only 8.1 - 8.2. <All sounds good.> Current tank inhabitants are 1 maroon clown, 1 blue damsel, 1 bar goby, 1 Banggai cardinal, and an oddly well behaved domino damsel that I cycled the tank with. All fish are doing great and even found a small colony of polyps (green centers with brown tentacles tipped green - I.D?) <Sounds like Zoanthus.> growing on the backside of a piece of LR. I acclimate the snails according to your book, and they seem to do really well the first few weeks. Then slowly, the snails fall off the rocks, and lay still upside down for days (I assume they're dead and not admiring the lights above). I started with 3 snails, then another 3 - all dead. I thought it was copper from some "unknown" source and had it tested for a second opinion at the LFS - not a trace of copper. I've never treated my main tank w/copper, but have it on reserve for my QT in case I need it. My second purchase of 3 snails came from a completely different store because I wanted to make sure they were healthy, if the original 3 were not. Same results. Other problems included green hair algae which has diminished with an adjustment to my skimmer (more flow), manually picking and siphoning, and reduced feeding. I plan to add some Caulerpa into tank soon. I don't think the snails are starving because I can see a "cleaned trail" on the LR as they graze. <Neither do I.> They just seem to suddenly slow down after 1 week, slow down after 2 weeks, and by the third or forth - they fall off and lay still (upside down). I've even banned smoking in the entire house 2 weeks ago because I thought the skimmer was sucking in 2nd hand smoke from the air and injecting it into my water (do you think they have a nicotine fix?). <No> I'd like to add more snails and maybe a cleaner shrimp, but want to figure out this problem before adding anything. I have a feeling that it has something to do with my water changes. <Not likely. Salinity shock is a concern, but does not seem to be your problem.> Any ideas? <Yes, actually a rather simple one. I am guessing you have Astrea species snails. This is what most "turbo" snails sold in the trade are. Astrea, for whatever reason, are incapable of righting themselves after falling off of the rock and landing on sand. They lay there for a while until they die. The next time you get some snails, try to find some "Turban" snails. They are larger and their shell spirals sideways versus the Astrea snails shell that rises up to form a cone.> Thank you for your time and apologize for the long email, but I wanted to give you the "full picture". <No apology necessary.> PS. I think I glanced somewhere that you have another book out. If so, what is the title? Need to add to the library. -Bob. <Bob has written "The Conscientious Marine Aquarist" and "A Fishwatcher's Guide to the Tropical Marine Aquarium Fishes". Bob, Anthony, and I are currently working on another book with a working title of "The Best Reef Fishes for the Modern Marine Aquarium." -Steven Pro>

Re: Strange thing growing on clam shell I just sent the image earlier and I'm attaching it right now. Thanks. <no worries at all... your hitchhiker is a harmless Vermetid snail. They are sessile (non-moving) filter feeders... and you may notice that they secrete a mucus web which they issue to collect microorganisms before sucking the web back in for digestion. A fascinating creature. Enjoy. Anthony >

Re: A mysterious end Hi gentlemen, <cheers> Thanks so much for your help with this. In fact, I did add about 12 Astrea snails to the tank over a week ago without quarantine. That's probably the answer.  <Ahhh... yes. There is a much higher incidence of parasitic disease with Atlantic livestock in aquaria (in this case carried in the water with the snails)>  Unfortunately I'm not sure how to go about quarantining snails.  <all things wet should be quarantined...live rock, plants, corals, snails, fishes, etc). In many cases (most) no medication is necessary... just a 4 week period where most pathogens will be expressed, die and/or wane without a viable host> What would they eat to stay alive in a quarantine tank?  <the same thing they in in the other glass aquarium (your display): diatoms off the glass, Nori seaweed from you... grazing on a small piece of live rock added. Think of QT as more of an observation period than anything.> My main tank has plenty of algae to munch but pickings are pretty slim in quarantine. <algae wafers, Spirulina tablets, etc. Many options here my friend> Thanks again, Andy
<best regards, Anthony>

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