Clam killer on the loose - 1/17/05
Guys (and girls?), <We do have quite a few men and women helping out here....thank goodness!>
First off, your web site has to have the most information on saltwater stuff in the whole internet.<Totally agree with this statement and I would like to add that it is a totally free resource paid for by Robert Fenner and our sponsors. Websites are not free but he pays for this out of his own pocket. Also, let's not forget that the people who volunteer pay for it with the time they donate. We should also thank our sponsors. To keep this site free we would not be anywhere without their grand advertising monies. Lastly but not least of all, you the collective readership. Without the questions, retorts, challenges, donations (time and/or money), and suggestions, we would but merely exist on the web! Thanks to everyone.> If there is another site I've not found it. Thank you for your time that you donate! <Maybe you could donate your time too??? We are always looking for a new volunteer or two =)>
On to the question. I had a Crocea clam (6") Super Colored from Live Aquaria that lived on the sand and it was beautiful. <Crocea clams are gorgeous but also happen to be the least hardy and most sensitive to many environmental changes, in my opinion.> I had it for about 6 months and then one day I noticed what looked to be a white fleshy chunk laying on the sand behind the clam. <Sounds like the foot was severed off. (Yep, clams have a muscular foot for adhering to rocks and whatnot)> It appeared to have come from the back side of the clam <Underneath actually> and I found that I was able to look through the clam where as I was not able to before. <So sorry to hear about this. I have heard they will develop a new foot but that is usually in ideal conditions. Too many predators to enter through the gaping hole left behind after the foot is missing, though> After another week or so the clam regretfully died (much to the joy of the hermit crabs and snails). <No kidding. Have had this happen twice in four years and the animals seem to rejoice and revel in such sorrow so to speak> At the time I chalked it up to "natural" causes (poor animal husbandry?). <Possible but does seem to happen more often with this species of clam> After about 3 months I got another clam (unknown type, not crocea, about 3") because it came with a rock I wanted. <Hmmmm> This was about 4 weeks ago, it did not live on the sand bed but up on the rocks. <Sounds like it could be a maxima> Anyway, I looked in my tank this afternoon when I went home on lunch and seen another one of those white fleshy chunks on the bottom of my tank beneath where my clam is. <Weird, So something bored through the rock to get at the foot??> To say that I am worried is an understatement. <Understood. I don't even know you or your clam and I am extremely concerned. Not the least of which the Tridacnids are very expensive animal.> I was miserable when my first clam died and I hate for my second or any others to die also. <Understood>
My tank is a 75 gal with overflow to 29 gal sump. <Very good. Do you quarantine?>  I have almost pristine water conditions. <Says you. Do you continually test for said pristine conditions? What do you base this on? Just curious, as I know nothing of your water conditions or your skill as a hobbyist. You can pretty much find ideal water conditions on our site if any are in question =) See here: http://www.wetwebmedia.com/ca/cav1i3/Clam_care/Clam_care.htm this was written by our friend Barry Neigut of Clamsdirect.com. I personally buy all my clams from him. A wonderful resource and a super guy to boot.> In my tank I have had the following during both incidents: 1 yellow Tank, <Tang? No problems> 1 3 stripe Damsel, <Nope. He would likely be OK> 1 blue devil Damsel, <Great little fish. Likely not the culprit> 1 coral banded shrimp, <Hmmmm....probably not but might keep an eye> 2 cleaner shrimp, <Nope. Fine> 1 horseshoe crab, <Cool. Love those little bugs> 1 orange sand sifting snail, <No worries> many hermit crabs <Suspect if large enough> and many snails (Trochus, margarita, turbo, Nassarius...) <Absolutely not but there is such a predator in snail form....the Pyramidellid snail> 1 emerald Mithrax crab (with one claw), <Be afraid....be very afraid...I don't trust 'em> many Pulsing Xenia (both Pom-Pom and the silver thinner kind), <Nope not at all> frogspawn, and several other types of corals and polyps. <Not likely culprits but do keep them from stinging the mantle by putting some space  between the LPS and the clam> I hope I didn't forget any important info. <Only you would know ;}>
I really don't know what is killing my clams but I really want to find out so I can enjoy having them in my main tank and not have to worry about their safety. <What about a tank aimed at keeping these beauties? Maybe a forty or 50 gallon with a 400 watt metal halide and some live rock in the sump? Add a heater and that would just about do it.....> I am going to move the clam to another tank (27 gal bow front that has been running for 3 months) tonight. <Excellent. This is a great idea provided water parameters are very similar as well as lighting and the lack of predators.> Hopefully it will be safe in there! <I hope so. No guarantees though with clams. Not much else to add but maybe keep an eye on your shrimp and crabs. Water parameters are a must for healthy clams. Let me know what you find out or how it turns out. ~Paul>
Thank you all in advance again for all of your hard work and time!
Randy

New T. Crocea and Possible Mantis Shrimp(s) 4/9/04 
Hi Anthony (or fellow knowledgeable Crew mate): 
<howdy!> 
I hope all is well with you. 
<and with you in kind> 
It's been a while but I have something to ask. A couple of weeks ago I placed a beautiful T. Crocea on the bottom of a tank with a sugar-fine sand bed. (I'll skip the tank parameters since they don't relate to the question at hand.) I placed him on a flat rock buried in the sand as I have read one should do. 
<yes... excellent> 
A few days ago, I noticed that the rock was uncovered around the clam, so I carefully scooped some sand back around the base of the clam to cover the rock again. I thought maybe the flow in the tank had uncovered the rock, or that the clam had blown the sand away at some point. Well, to my horror (okay maybe not horror, but definitely displeasure) I came down this morning to find the clam lying on it side in the sand and the rock even more uncovered. I thought at first that the clam had been trying to move and blown all the sand around, even though he was still attached to the rock by a thin appendage. So, I went into the tank intending to upright him when --- YIKES!! From the rock that the clam was sitting on came three darkish brown figures streaking for the live rock! I took a look at the rock the clam sits on and realized that it wasn't quite as flat as I thought. It has a small groove down the middle that goes directly under the clam. I can't think of anything these might be except mantis shrimp. Are there mantis shrimp that stay quite small or grow very slowly? 
<yes, indeed... some with a max size of 1" (2.5.cm)> 
These were only about 0.5 - 0.75" long and the rock in this tank is probably at least a year old. 
<ahhh, probably just amphipods. Unless you are familiar with them and can rule them out. Do find pics on the net of them (also in our Reef Invertebrates book)> 
Also, they swam instead of running along the bottom and moved very quickly. I assume mantis shrimp can swim when they want to do so?? 
<yes> 
Anyway, my new theory is that they dug and tunneled around the clam trying to get to his "soft underbelly." I am going to set a trap near the clam tonight, but I just wanted to check whether this sounded reasonable to you or whether you had other ideas. 
<no worries... the trap sounds like a good idea, indeed> 
Whatever they are, they don't seem "clam friendly," if you get my drift. They must go!! ...if I can catch them..! That's it for now. Thanks again for all your advice in the past. Take care, Greg 
<best of luck. Anthony>

Snail Hunting
<Ryan with you today.>
This is more of an observation/hint/tip on ridding your tank of Pyram snails before adding clams. <Great>  They, Pyram snails, seem to be attracted to the small Trochus intextus snails I got as part of a reef cleaner package.   As the Trochus move around the live rock at night, the Pyrams crawl onto their shells to possibly feed on these Trochus (I have never seen this but I suppose it happens).   When the lights go off, the Trochus come out and usually have a few Pyrams holding on near the bottom edge of their cone-shaped shell.   I just pick the Trochus out of the tank and rub the Pyrams off with my thumb and put it back.   I do not have clams at this time and the Pyram population has been substantially reduced using this method of hand extraction.   I had a small six-line wrasse in the tank and s/he wasn't making much progress at all (underachiever).   It nibbled at many things on the rock but I never saw it eat one of these snails.   Initially, some of the Trochus snails had a couple dozen tiny Pyrams on their shell.   Now I see one or two now and then. Pyrams are not attracted to any of the other grazer snails I have in the tank just the Hawaiian Trochus!  
<Very interesting observation.  I will post for others to read.  Thanks for sharing, Ryan>

Pyramidellid snails 1/24/04
Hello there.  I read your articles and FAQ a lot lately. What a great site, I've learned a great deal.
<Hi Loris.  Adam here.  Sorry for the slow reply.  Glad you enjoy WWM!>
My question is this. I'm interested in purchasing a Tridacna clam, but my tank has these tiny Pyramidellid snails (at least that what I think they are). The tank is as follows:
90 gallon reef tank
6 months running
3 ocellaris clowns
1 fire Dartfish
(eventually: regal blue tang, royal Gramma, mandarin fish, Kaudern's cardinal, Chromis)
1 scarlet skunk cleaner shrimp
1 blood red fire shrimp
a number of corals (hard, soft, polyps, etc.)
blue leg hermit crabs
Nerites snails
Everything healthy as can be.  From what I've read, a yellow wrasse (H. chrysus) will munch on the shrimp, a six-line wrasse will pick on the Dartfish and possibly the clowns.
<Both of these fish and others will prey on Pyramidellids.  My strongest recommendations for this job are the four line wrasse (Pseudocheilinus Tetrataenia) and the tail spot wrasse (Halichoeres melanurus).  All of these fish will do the job, have great personality and are attractive, but do have two downsides... they all can be a bit aggressive (especially when larger, and especially any Coris) and they are very effective amphipod predators.>
Is there anything out there that can control the Pyramidellid snails and be safe with the above mentioned?  Thanks for your time and help.  Loris
<Coris wrasses get quite large and aggressive.  The others may be a bit belligerent, but probably worth the risk.  Also, FWIW, if you have never had clams, it is doubtful that these are true Pyramidellids, but positive ID can be quite difficult.  If you can take a very high quality of the operculum of the snails, we may be able to figure it out.  HTH.  Adam>

Derasa Clam in trouble 12/4/03
I think there may be a problem with my 4 " derasa. Last week, I found what I have now identified (I think) as either part of or the complete byssal gland lying next to the clam... This clam has been in my care for the last year or so and has never exhibited any sign of a problem. It lies on the substrate and isn't attached to anything. Now the clam is showing signs of stress... Poor mantle expansion, slow to react, gaping. Anybody have any idea what the problem might be?
<could be predation (look for tiny Pyram snails like grains of rice) or bristleworms at night (inspect after the lights go out)... possibly a crab although more damage would have been/be likely. Then there is the issue of water quality: light shock from a recent and overdue change in lamps or a large water change/change of carbon that increased water clarity suddenly... clams are also sudden to a large influx of freshwater for evap top-off... or spikes of supplements to the tank that are not adequately diluted>
I've heard of larger clams expulsing their byssal gland but never 4 " ones and especially not T. derasa... Thanx Simon
<this last assumption is not correct, my friend... there is little discrimination by age/species for the expulsion of byssal matter... rather just a matter of necessity by individual when called for. Still... its not an unhealthy maneuver and signs of stress here indicate a larger problem perhaps. Anthony>

Derasa in trouble II 12/6/03
Anthony, Thanks for taking the time to answer. Unfortunately, the clam died ~24hrs after my e-mail. I  was not a happy camper.
<sorry to hear it>
The water parameters are all fine and out of all the inhabitants of my 110 gal reef, the clam is the only casualty.
<different tolerances too to stressors, and "somebody has to be first" as they say. Point being... don't dismiss the potential for a problem just because everything else currently looks fine. Without knowing your full water chemistry, I cannot concur with the evaluation of water quality>
(there's also a 6 inch maxima in there) No Pyramidellid snails or bristle worms either. There IS an elusive crab in there somewhere.
<yikes... indeed, no crab is truly reef safe>
He's grown quite big since my first sighting.(~1.5 inches of carapace) I know he's in there but I don't see him often.
<do bait and trap him. Should be easy enough (crabs are greedy). We have tips for doing this in the WWM archives and in our Reef Invertebrates book>
Looks like a type of crab I've heard called "shame face crabs" but I can't be sure. Maybe I should be trying to catch him...? Thanx again. Simon
<if it is indeed large clawed like a shame-faced crab, you can be assured it is a threat. Those claws are generally built for eating snails and bivalves/clams. Kindly, Anthony>

Clams In A Jam?
Afternoon all!!
<Hiya! Scott F. at your service!>
I have an issue with my two clams as of the past few days they are only ¼ open. I have had both for years and all other corals and fish are thriving. Is this common in clams. My calcium reactor is working throughout the day and all parameters seem fine. Of late the clams have been emitting some kind of mucus which I assumed was from the newly added calcium reactor. Any advise on why BOTH they have shut for the past two days??
Thanks Stu
<Well, Stu- it's hard to say exactly what your clams are reacting to, but it might be possible that some sort of water parameters are out of whack. Usual suspects include ammonia, nitrite, excessive phosphate levels, or rapidly fluctuating pH, not to mention the possibility of "chemical warfare" from stinging cnidarians that may be in close proximity to the clams. Did you recently change lighting? Are you using any new additives, "medications", or foods in the tank that could be a problem? Test the water again, just to be sure. In the absence of these as problems, the other possibility is that someone in the tank has started picking at the clams. Do check the behaviors of any of the "usual suspects" (i.e.; angels, certain wrasses, etc.) to see if this occurring. My advice when these kinds of seemingly unexplained anomalous behaviors occur is to use the old standby of a water change, coupled with use of aggressive protein skimming and activated carbon. Hopefully, with a bit of minor intervention, and the passage of time- things should work out fine, and they'll be "happy as a clam" in no time! Good luck! Regards, Scott F>

Cowries and giant clams
Hi,
<Howdy>
I added a giant clam to my aquarium a week ago.  It seemed to acclimate pretty well, and was generally being left alone by all others in the tank, until today.  This afternoon I found a cowry had latched onto the clams foot.
<Foot as at the base? The byssus?>
I didn't want to wait around to see if it was just passing by, so I moved it off and relocated the clam to a less vulnerable spot.   The cowry played dead for most of the afternoon, the clam seemed to be ok with the spot I placed it, so no big deal, right?  Now tonight I find the cowry is on the clam again.  This time it's stuck on the clams side.  Does he have the ability to drill through a giant clam shell with his radula??
<Not likely. Cypraeids don't prey on tridacnids as far as I'm aware>
  I have not been able to figure out if he's going to kill my clam or just give up and go away.  Please help.
thanks,
eve
<Very likely the cowry is simply "looking for food" on what it perceives as an "inanimate object". I would not be concerned here. Bob Fenner>

Blue cleaner wrasse on Pyramidellid snails 
Hi! I have a giant clam which has Pyramidellid snails on it. I introduced some blue cleaner wrasse knowing that wrasses eat these parasites. 
<wrasses do eat them but not cleaner wrasses. A six line or four line will do the trick> 
Is blue cleaner wrasse good in eating pyrams? 
<no> 
When is wrasse more effective? day or night? 
<depends on wrasse cleaner wrasses more active during day> 
I am planning to do a little experiment on the feeding habits of the blue cleaner wrasse that I bought. Do you know the rate of feeding of this wrasse on pyrams? 
<no feeding> 
I want to know if the result of my experiment will be correct. Thanks a lot! I want to be a marine biologist someday... 
<Thanks for the question Mike H> 

Missing derasa clam! 10/14/03
I added a derasa clam to my 44 gal reef tank a few months ago.  It didn't seem to like the spot I originally placed it in--stayed tightly closed--so I moved it to a corner of the tank, on the bottom where the light wasn't as intense.  It appeared to like that spot, opening about half way, closing in response to shadows, first facing the glass on one side of it's corner, then the next day it would be facing the glass on the other side of its corner.  In other words, active, apparently healthy.  
<agreed>
I dose the tank with a teaspoon of calcium and 8 drops of iodine daily, per supplement label instructions.  I feed the tank DT's once or twice a week, and use a syringe to shoot some DTs near the clam's intake.  
<do go easy on squirting any supplements directly at filter feeders... including such foods>
This morning, when I fed the fish in the tank their Mysis shrimp, the clam as usual was open about half way and responded to the shadow of my hand.  About 5pm I passed the tank and stopped to watch a minute.  The clam shell was gaping wide open and the clam was missing!  Where did it go?
<clearly was predated by something. A crab in the tank is the most likely candidate. Do trap for one at night with a small glass jar and a satchel of bait (heehee... food clam in a nylon bag or piece of boiled nylon stocking) inside... to see who the culprit is. Happy hunting... sorry about the clam too my friend. Anthony>

Gaping Crocea - 10/07/03
I have a 5" crocea which is gaping, the mantle is recessed, the inlet siphon is stretched as well as other spots on the mantle which looks like skin being stretched and ripped, the outlet whole that used to stick out like a nipple no longer does, just a hole, and when you look in the inlet siphon you can see the sand on the bottom of the tank (it's no longer enclosed. water parameters are ok, any tell tale sign? <Well, the sign to me is this clam will not, in all likelihood, make it another 24 hours. Don't move it though. Leave it be for the now. There isn't much known in the way of clam mortality per se. They seem to waste away quite quickly and for no reason. There are a great many theories, though. Read through our site on clams: http://www.wetwebmedia.com/tridacnidart.htm go through the links. Also, we have a friend of the site Barry Neigut of ClamsDirect.com, who not only has a forum on his site for troubleshooting clams, but he sells, and even consoles problems with clams via email. Give him a try as I am sure he deals with more clam problems in one day than we hear about in a month.> is it dead? <Possibly a goner> sorry for not giving more info <No more info to give. It is said that without the right sized foodstuffs (usually seems to be a natural occurring type of food) most clams last for a year or less in a tank. What I take from that, is that clams need to be fed at some level. There just isn't enough nutrition derived from photosynthesis. Something to keep in mind. Check Barry out!! -Paul> 

- Everyone's Favorite Snails: The Pyrams! -
My really nice Tridacnid clam has not been looking so good for the last week.  He is about 3 inches long.  Today I found about 6 Pyramidellid snails eating on his shell. <Very common on farmed clams> I removed them all, the were really small about half the size or less of a dried grain of rice. <Pyram snails, woohooo!> My question is, is it too late? <Depends, if everything else is in good shape and it's not too far gone, it should be fine. Keep checking every day or so for a while for any stragglers or egg-masses. It's also easier to check at night when they'll be actively feeding in the open> He is still expanding but the tissue does not go beyond his shell like it use to.  Anything I can do?  I make my own Phytoplankton so I am upping the amount to about 1/2 cup in the morning and 1/2 cup at night in my 125g reef. <Sounds like everything should be ok, although the clam appears to be pretty stressed by the whole situation. Just keep an eye out for more buggers and remove as needed. Good luck! -Kevin> Thanks  Larry

Bleached spot on clams mantle- 5/28/03
G'day guys,
<cheers, mate>
Just a few quick questions regarding thistles and a clam.
<and I will counter with a question right off the bat: what is a thistle? The common name is not familiar to me, my friend. I browsed several Australian message boards too (keyword searched) wondering if the name was colloquial and came up empty <G>. Tell me more about what kind of organisms this is, please>
Firstly the clam in my tank has grown considerably over the past 6 months.
<often so... as much as 5-10 mm monthly is not unheard of for T. derasa and T. gigas in particular>
A small area on a flap has lost its pigment from brown speckled to white. Is this to do with this area not getting the light??
<not likely... or not a good sign if so. It seems surprising that any tissue lies settled on any single part of the mantle long enough to cause such a condition. Do you have enough current to keep the mantle of this clam (as with coral polyps) flowing nicely? If so... we need to seek another explanation>
As this area is actually hidden when the clam is fully opened. When it shuts you can notice the white section which
is only 2cm. Any advise as it doesn't seem to effect the clam but takes away some of the beauty.
<it can/will be a problem in the long term though. Beyond current, aged lamps (or those with salt creep, dust, dirty lenses, etc) suffer the clams as the light degrades... the weakest parts of the mantle in turn are the first to show signs of stress/bleaching>
Lastly thistles seem to be hard to keep in an aquarium. Why is this and what are the ideal conditions for it to survive. eg: placement in the tank and food sources etc?? Thanks
Stu
<as per above on the thistles, my friend. Kind regards, Anthony>

Gaping clam.. take a sniff
Hey everyone!  I ask you guys so many questions I feel like I should send along a keg of beer!  Maybe one day I will have the opportunity to repay you for all the help you have given and likely will continue to give, but for now I hope that my passing on information to those less knowledgeable than myself and keeping my mind open to those more knowledgeable will suffice.
<actually... lets get back to talking about that beer. Ahem... oh, sorry... Yes. Your question <G>>
Two questions for you this time accompanied by a picture.  It is about the clam again, but this time I am hoping the picture will show what I was describing in more detail.
<it does>
T. squamosa.  About 5" long, 4" wide 4" tall.  Coloration is fine, but not accurate in the picture.  In reality it is a nice golden/rust color.  The central fading has regained about 50% of its zooxanthellae since I got it 7 days ago (probably expelled some zooxanthellae during shipping - shipping water had some minor discoloration).  
<understood and common with imports... but not domestically shipped clams. What happened? Coast to coast on the airlines in even inclement weather takes only 6-9 hours. For bleaching to have occurred, the animal would had to have been subjected to an extreme of temperature or a delay. Was this the case? Please don't tell me this was clam shipped via overnight carrier instead... Ughhh! Very few organisms if any should be shipped that way (discussed at length in my book... I'll excerpt it for anybody interested)>
Initially I was told by several people (based on written descriptions, which were/are lacking) not to worry about my clam, but something just doesn't look "natural" so to speak.
<normally I would have agreed with them as it is most often the case... but your picture helps, and your clam is not feeling well (gaping inhalant siphon... the beginnings are clear to me)>
The two questions are:
1.  Is the inhalant siphon gaping?  
<yes... just starting. And I have laid eyes on thousands of clams... literally (as an importer for wholesale)>
If you look closely you can see the edges of the siphon are rolled back a little bit.  
<agreed>
This has been progressing more every day I have had it.  Right now the inhalant siphon is the size of a half dollar and almost perfectly round.  Also, there are no tentacles left to speak of.  Barry had the clam for 6 weeks and the quality of his clams is reputed to be excellent (and I have no doubts about this),
<and I also agree with this>
but do you think maybe the shipping was just too much stress?
<depends... if we are talking New York to California on Delta... 4.5-6 hour flight... 2-3 hour recovery... 7-9 hours total. No problem even if New York was cold. However... if you ship FedEx Premium, for example (and most people do not pay this extra-extra overnight fee... but take the "by 3PM" option)... the animal is in transit for a bare minimum of 14 hours (usually closer to 20 hours) and almost every bit of that is at ambient temperature... whatever that is (they pay for no climate control for planes, trucks or warehouses.. can't blame them... they are not in the livestock shipping biz). Again, 14 hours cold is a best case scenario... if the office closes at 8PM, and if the clam was packed outside their door at the last minute (Ha!)... and if the clam makes it into your tank by 10AM next morning. Overnight parcel services are not scaled for livestock and many marine creatures die this way. I just don't see why some merchants still use them>
At night it is able to partially close its inhalant siphon.
2.  Is the siphonal mantle spread too wide?  It looks stretched a little bit, especially right at the top of the inhalant siphon.
<agreed>
I'm wondering if the adductor muscle is weakened at this point and it cannot maintain a more closed position (it can definitely slam its shell shut if it wants, but it doesn't do this unless I'm really messing with it).
<what was the water temp when you got the clam and how long would you estimate shipping took?>
I should add when I removed the clam from its shipping bag it wasn't completely closed then either.
<no biggie at that point>
Everything else about the clam seems fine.  Quick reactions to light changes, shadows etc.  When it wants to it can completely close its shell.  At night it pulls its mantle in and closes up a little bit.  I saw a few Pyramidellid snails, so I picked those off.  
<no biggie... common and controllable>
Today I pulled the clam out and saw a small orange mass on the bottom so I promptly took my nifty Oral-B toothbrush to the whole clam and made sure to get all the orange off, which I am assuming were snail eggs.  
<correct, possibly>
Also while it was out I smelled it (and I got squirted right up my nose for my efforts, but it was funny) and it smelled just like it should - fresh marine/fish smell.   
<dude... you are weird <G>>
Also my six-line finally made it into my tank and within 10 minutes was circling the clam and picking at the shell.
<maybe it was looking to sniff the clams bunghole>
Presumably and hopefully at the snails.  Also, I have stayed up fully two nights in a row watching for predation.  None.  
<good to hear>
I read a post on Reef Central (http://www.reefcentral.com/vbulletin/showthread.php?s=&threadid=81032&highlight=gaping) that seemed logical.  Basically he tied the clams shells shut.  
<The thread is interesting... but I have some concerns with the reasoning and logic of it at length. Something to discuss at length over a beer <G>>
I don't think I would want to tie them completely shut as he did, but do you think, IF there is even anything wrong with the clam in the first place, that this would be something worth trying?
<weakly if so>
Once again thank you kindly!  Yours is an invaluable service to the hobby and to the creatures entrusted to our care! RVM
<with kind regards, Anthony>

Clams and Pyram snails and angry little wrasses
Anthony (or whomever else, Anthony just seems to get all my e-mail hehe), I hope all is well and pleasant!  
<and with hope for you as well>
I'm planning to get my open water dive cert. before this summer and hopefully take a trip to Australia and the GBR.  I absolutely cannot wait!  
<outstanding!>
Well, onto the point of this post, which is quite the direct opposite of the excitement of diving in a natural, well-preserved reef. Interesting observation inside my clam.  I'll paste here what I posted on RC and sent to Barry.
-------------------
Looking into its inhalant siphon you can see the gills and internal body structure.  Well, right between the gills, there is the fleshy (could not find the correct anatomical term) divider which separates the guts, internal organs, exhalant chamber from the inhalant chamber.  This flesh is translucent, that is, you can see through it to a degree.  Well I'm peering in at my little shrimp today, doing whatever it is they do in there, and I see a black shadow on this fleshy divider.  I look closer and come to find it has the outline of a 2mm (rather large) Pyramidellid snail.  I can see the foot outline and the shell on top of it.  No mistake as to what it is.  
<alas, yes... they are too common>
I can see no way to remove this pest without killing the clam.  
<actually no... you can have a soft bumper (foam) ready to slip at the splayed opening of the clam to keep it pried open and use surgical tweezers (pointed tip) to extract the snail perhaps... like the game "Operation" as a child... except without the buzzers>
I am guessing this is why my clam usually seems stressed.  
<Oh, ya>
It is probably also why the mantle surrounding the inhalant is bleaching out.  
<hmmm... stress here>
There are no snails on the outside of the clam and no eggs on the bottom.  I figure even just one of those snails sucking away at its insides could do it in though.  
<agreed>
This bothers me because there is nothing I can do.  
<maybe we can find a 4 mm six-line wrasses with an attitude to swim into the clam's body and kick that snail's ass <G>>
Generally all I'd have to do is remove this snail and all would hopefully be well (barring other problems/diseases I am unaware of) but I cannot. If anyone has any advice at all please do share!
<use the bumper and tweezers instead>
*edited in*
I now see 4 simultaneously.  One is still the 2mm one, it hasn't moved much, and there are 3 others, varying from .5mm to 1.5mm.  *sigh*  I'm frustrated!
------------------
Thread is here http://www.reefcentral.com/vbulletin/showthread.php?s=&threadid=142032
--------------------
Please do tell me your thoughts on this.  Is it possible this might be the "clam disease" that has been wiping out clams over the past several/many months?  
<I suspect they are unrelated>
Freshwater dips seemed to have helped in some of these cases.  Obviously the freshwater killing the snails within the clams could account for the success here.  
<risky... but possible>
I believe Minh Nguyen had much success with freshwater dips.  
Either way this might be something worthwhile to put on your Tridacnid FAQ so others might know what to look for.  
<will do... with thanks. Anthony>

Waiter, There Are Snails In My Clam! (Pyramidellid Snails)
I have a 6" T. Derasa. A few days ago I noticed that it wasn't extending its mantle as much as usual and its incurrent siphon was opened much more than usual. I picked it up and it had about 30 Pyramidellid snails attached to it.
<Yikes!>
I was able to pick most of them off but there more today. What can I do? I can temporarily move it to a different tank, but it only has NO fluorescents on it. I do have a sixline wrasse that does
a good job of getting the snails that attach to the clam up towards the mantle but it can't get to the ones that are attached to the bottom. Thanks, Eric
<Well, Eric, I think the sixline wrasse is a good "assistant" for you, but manual extraction may be the best way to go here. I you want to move the clam to this separate aquarium, you can compensate for the NO fluorescents (at least for a short period of time) by placing the clam higher up in the tank. Just keep an eye on this clam...Ya know- I'm a major quarantine freak (even for clams and inverts)...a nasty Pyramidellid snail infestation is a great lesson on the value of quarantine. As you are finding out, these little @#$%#@ snails are a real drag to get rid of once they get a foothold <G> in your tank...quarantine can help. Just stay on top of things...keep inspecting the clam daily, and, in time, hopefully you can end this infestation! Good luck! Regards, Scott F>

"Gaping" Squamosa - 4/2/03
Hi there WWM Crew... <Hi there. Paul here for a few>
I hope this email finds you happy and healthy today. <Actually no, I have a horrible cold. A little slow on the draw, but otherwise fine>
I have a question regarding the well being of my new T. Squamosa. <OK. Go for it>  Is it normal for them to gape for the first few days following acclimation? <Well, in my experience they can "gape" anytime and usually recover. You just never know though. If I remember though it seems to me that Squamosa kinda "gape" anyway.>  The lil guy was delivered Tuesday and was acclimated over a period of an hour plus. <Well, nice but did he go into an acclimation tank? In any event sounds fine>  I ensured that I added some tank water, via a turkey baster, over and over until the container was full. <very well>  I then dumped half and did the process over again.  After more than an hour, I finally placed him on a piece of empty clam shell just under the substrate for him to become accustomed to his new environs. <Very good. Lights off?>  Other than a troublesome wider inhalant, it seems okay.  Color is good and mantle expansion seems normal for a newbie. <Sounds about right>
The packaging from the seller was wonderful. <Who is the seller if you don't mind me asking?> Many air filled bags of insulation surrounded the live specimen bag. <Cool>  There was 2 inch foam lining the box and two heating pads therein. <Good> The water temp was not all that cold, considering it is New England. <What does that mean?> I waited at the door all morning for delivery and acclimated it right away. <Very responsible>  It was en route for a short period of time (Next state overnight - FedEx) <Still could be a lot of handling between seller and buyer>
The reason I chose Squamosa is that I have power compacts. <ahhh, good choice then> Everyone I speak with says that my 6w/per gallon should be sufficient. <Definitely>  I've read the book "Giant Clams" and it too says that Squamosa would be my choice. <Very good. Glad to hear you on board as a Conscientious Marine Aquarist> I was planning leaving him on the substrate, but your opinion on this is appreciated as well. <I would leave him there for about a week minimum. Then slowly start moving him toward his final resting place. In the wild though, these guys are usually found on the substrate. So he may be fine where he is. If he continues to gape though I would definitely hold off on moving him anywhere. Clams have been known to crash and die in about 12-24 hour period, so keep an eye on him. Oh yeah, definitely let the seller know he came to you in this "gaping" condition. From the picture though he looks pretty good!>
I may just be paranoid.  Others have told me that Squamosa have larger siphons as compared to other Tridacnids. <True> I'm used to seeing Maximas which rarely "open wide". <Also true. Healthy ones anyway> I've attached a picture for your viewing. <Looks good>  You can email me direct if this is not FAQ worthy. Definitely FAQ worthy. Did you get a chance to read our FAQs? Lots of good info there. you can always contact Barry Neigut at ClamsDirect.com as he has quite a good amount of experience in the various hobby clams.>
Thanks for all your help. <My pleasure David. I am sure your clam will thank you for your research as well!>
David  

Clam exudation 3/27/03
Greetings!  I have a blue Tridacna maxima, about 5 inches below the surface of the water under a 175W MH with 40W of fluorescent actinic.  The clam is about two years old.  Recently I have noticed that in the evening, I see a very thin brown strand of  (I assume) zooxanthellae algae coming out of the exhalant siphon.  
<could be... sometimes they are expelled naturally in small packets, other times induced by stress (increase in light as with new bulbs or clarity as with water change or sudden use of carbon)>
The clam is well extended and looks great.  Water parameters are great and unchanged, except that I recently (1 month ago) noticed that the pH was dropping to 8.00 during the night.  I slowly used Reef Buffer to raise the pH to about 8.45 during the day, dropping to about 8.30 at night.  Salinity is 1.025 and nitrites are zero, and nitrates are 5ppm.  
<all good>
I use PolyFilter and an Urchin Pro.  Is this algae discharge normal? thanks tom
<likely no worries at all. Be mindful not to overfeed (at risk of clogging gills) with liquid supplements too. Best regards, Anthony>

Re: Clam exudation 3/27/03
Thanks for your response, Anthony.  I have been feeding liquid food, perhaps a little bit more than usual.  This afternoon I noticed some bleached spots on the mantle which weren't present this morning.  The mantle is open/out.
<not good signs at all... and rules out coagulated food from overfeeding as the primary. Stress from a physical parameter is more likely now... the sudden influx of a larger than normal bit of freshwater perhaps for belated evap top-off? Dosing supplements in strong concentration near it at the top of the tank (sans dilution in sump or strong stream). Hmmm... many possibilities. Predation is more common in general but would not expectedly cause the bleach spots. Instead we are looking for stress or disease here. Perhaps a new fish or coral added recently without QT brought in a pathogen>
Any suggestions? thanks, tom
<watch nightly for predators, but otherwise do not disturb while evaluating water quality. A water change is usually helpful too (dilution of the unknown). Anthony>

Stressed no more... better Tridacna days 3/28/03
Anthony, Sorry to have raised the alarm.. My otherwise beautiful, talented and intelligent wife mistook the golden mantle highlights as "bleaching".  
<ahhh... no worries. An easy mistake to make under the circumstances. Kudos for her attentiveness indeed>
The clam did put off some brown strands of material, which I was earlier asking you about.  I had gone out of town, though, and I asked her how the clam was doing and whether there was any bleaching.  She reported back, and I emailed you again.  Ah well.
<better days ahead for sure>
Thanks for your very prompt, thoughtful and caring response.  You are a credit to the hobby! tom
<its truly redeeming to hear you say so, my friend. Thanks kindly and best regards! Anthony>

Clams
Hi Bob,
Want to pass something by you. You may or may not be aware that a lot of people are losing clams after buy clam/s that are coming from Pohnpei so I have been told. 
<Have heard this from others>
The people that have contacted me are saying that once they placed this clam in their tank with a day or so the clam dies and then a chain reaction starts, some have lost clams that they have had for several months or years. Some think it is a bacteria infection. My question is, if indeed this is correct will the bacteria infection
remain the tank or even stay in the LR or substrate. Some people have reported good luck using Doxycycline as a treatment.
<Have also heard this>
Do you have any information or suggestion on this subject?
<Will send to others here>
All is going well on this end. Thanks for you help in the past and yes ClamsDirect is doing well thanks to some of your help. :)
<Very good to hear/read of your success. Be chatting, Bob Fenner>
Best Regards, Barry

Derasa Clam Problem
Bob, I have about a 5 inch derasa clam and a 2 1/2 in maxima clam. I have had the derasa for over a year and it has been doing very well. I just recently added the maxima about 3 months ago. To give you some info on my system, I have a 125 gallon reef tank with a mixture of hard and soft corals. I have VHO lights. All of the necessary parameters for good water quality are where they should be. Both of my clams are on the floor of my tank. About two days ago I noticed my derasa clam was leaning to one side, which I didn't think much of because it sometimes would tip over because a fish would swim by and spook it. I went to straighten it up with a little stick I have like I have done hundreds of times before and noticed that the clam didn't close right away from the contact. As a matter of fact, it almost seemed like the two halves of the shells were not aligned anymore either. When I tried straightening the clam by lifting the one half of the shell it sort of moved independently of the other one. This seems to have gotten worse over the last few days. The mantle is not receded or anything and still has good color. The clam just isn't opening up fully like it used to and the what holds the two halves together seems to have lost the strength to hold itself together and close fully. The clam is showing no signs at all of being attacked by anything. I see no holes from worms. There were a couple of those supposedly reef safe snail with the small, flat, purple and brown shell that only come out at night hiding underneath the shell but I'm pretty sure these are not doing anything to the clam.
<if you are referring to Stomatella "paper-shell" snails then I agree>
I know it may be hard to determine the cause of the problem but do you have any idea what would cause this? 
<I'm concerned if the clams were kept on the sand bottom without a rock buried underneath them. Attachment to a small rock is critical... it prevents snails, worms and crabs from preying from below through the vulnerable abductor port/muscle. Pyramidellid snails are very tiny (like grains of rice as adults!) and very damaging over time. Another concern I have is the lack of light at depth... I fear the clam has been starving from inadequate light. As bright as VHO lamps seem to be... they are very weak at depth: they are only good for the top 12" of water and degrade rapidly below that. So if the clams are at the bottom of an 18-24" deep tank... they are not getting enough light. Starvation may be an issue here>
Is there anything I can do to reverse whatever is happening to the clam. If not, should I immediately remove it from my tank before it maybe spreads to my other clam which sits right next to it? 
<unlikely to be contagious... look for Pyram snails and other predators (crabs, bristle worms) and move the clams to within the top 12" of the surface>
I appreciate any help or advice you may offer on this problem. Thank you, Gianluca Carpinelli
<best regards, Anthony>

Clam
Bob,
Wanted to share something with you that I was thinking about while I was sleeping.
<We've got to stop eating licorice and pepperoni pizzas before dossing down>
Had a Black Maxima that I placed in a tank and one of my fish attacked him several times and after the third attach the clam gave up and gapped the size of a quarter. Not knowing what to do, took the clam out and placed him in a quarantine tank with minimal light, no substrate and did some feeding. After 8 days the clam recovered fully. I will just about guarantee that if I had left him in the main tank being so stressed that the critters would have finished him off. So my observation is that if you have a clam in distress and place him in a stress free environment so that he can recover he will most likely do so but leaving him in a stressed situation no chance of recovery. Have done this several times with 98 % success.
<Thanks for this... you gapper, gipper>
Thought this observation was worth passing on. Not a writer but I think you get my point. :)
<Yes... will fwd to the fellow-writing boys. Bob>
Regards,
Barry, www.clamsdirect.com

Clam Disease?
Anthony, I recently lost 2 gold Maximums to what I have been told is Clam Disease. Several people tell that where I purchased them has had tanks that are infected. What is this mysterious clam disease and just how can I eliminate it from my system. Should clams be freshwater dipped? Thanks Mark
<I would almost never recommend FW dipping clams. I am also quite doubtful that whoever suggested your clams had "clam disease" has a clue (however well intended they might be). The higher rates of mortality from select clam shipments recently have been limited more to batches rather than a locale/source or specific pathogen (despite folks in the industry looking for an excuse for their poor husbandry as retailers or wholesalers). We have seen this many times with other animals. There is likely no new disease... just poor handling by at least one of the bigger players in the chain of custody (importer, LA wholesaler, etc). If a LFS has a "clam problem" then they simply have water quality issues. To answer you question, bud... there is no definitive ID of a specific pathogen for this recent "condition". Preventing and eliminating it is simple: QT all livestock for 4 or more weeks first. Containment and control. Never add any fish, coral, other invertebrate or plant to your tank without a 4 week QT. It's Russian roulette if you skip QT. No meds here... simply good water quality! See the references to feeding ammonium or nitrate to clams in my coral prop book or better (!) Daniel Knop's Giant Clams book. Do this in QT to power feed the clams. Natural resistance is better than anything we can offer Tridacnids. Medicating invertebrates is still in the dark ages. With kind regards, Anthony>

Tridacnid
Hi, I have a 5" crocea that hasn't opened for a little over a week. I was going to be getting a rose leather, a green bubble and a Galaxea on Friday. My flame angel and my yellow tang, I just noticed, have been picking at the clam when it tries to open a half inch. I need to put the clam in the quarantine that I was going to use for the corals when they came in. I e-mailed the sender to delay shipment so I can use the QT for the clam. Is there any type of food that I need to feed the clam while in the QT?
<Phytoplankton could be helpful, although I have heard that feedings are particularly important for juvenile clams. Your 5" Crocea is near full size and could probably live on very little food.>
Or should I just let if feed off the light in the QT while it recuperates?
<Depending on how long it is there will determine if additions are needed. Daily, small water changes from the main display could provide the clam dissolved organics to filter feed.>
How long do I need to put it in the QT to bring it back to health before I put it back in the main tank?
<You cannot put it back in the main tank until after the Flame Angel and Yellow Tang have been removed.>
Thanks for all the help, Jeff
<Good luck! -Steven Pro>

I Have a Question About a Clam
Hi Bob or whoever is taking your place if your not there;
<Steven Pro right now.>
I've never had a clam before but I'm curious about something I saw on all the clams I have been looking at in the local stores. I believe based on research that these clams are Tridacna derasa. I understand that each has its "mouth" but I'm curious because most of them seem to have a split on the other side of the clam. Is this normal?
<Yes, clams have both an inhalant siphon and an exhalent siphon.>
Are these clams in distress?
<Nope>
Do they all get this split?
<Yes, what goes in must come out.>
Are they forming another mouth?
<No>
Are these specimens to get or to avoid?
<There are other factors to consider. Daniel Knop has written an excellent book, "Giant Clams". Please pick up a copy for your education prior to purchasing any clams.>
Thanks, Mac
<You are welcome. -Steven Pro>

Quarantine Clams
Good morning/evening Steven,
<Good afternoon.>
If I was only to keep one clam, would that reduce the need for quarantine?
<Reduce but not eliminate. Always best to follow good husbandry practices.>
Does this creature carry organisms which may also be dangerous for fish/corals?
<Possible infectious agents in the shipping water.>
Having read quite a bit about clams/care/diseases and predators on your site and others, how would I know if some predator snail/worms which are not commonly visible (remain hidden in attached rock) were present, short of seeing the clam die?
<See if you cannot find Daniel Knop's excellent book "Giant Clams". He has written an extensive section on identifying and treating various "diseases" of clams. -Steven Pro>

What Needs Quarantined?
Greetings,
Do you need to quarantine a maxima clam?
<Best to quarantine anything.>
If so, why and for how long?
<Generally two weeks minimum with one month being best. Clams sometimes carry parasitic snails that can attack and kill clams in the confines of aquariums.>
How do you get around the need for metal halides in a quarantine situation?
<You really can't. Again, it is a matter of investment. Clams are not cheap and if you have several, bring in a new one that is infected, and then lose all your clams, you will wish you had quarantined. It is actually a quite frequent story that you hear.>
Do you need to quarantine soft/hard corals?
<Yes, and live rock too.>
Many thanks, Michael
<You are welcome. -Steven Pro>

Stressed Out Clams?
Dear WWM Crew, Gentlemen, how are you? 
<very well with thanks!>
I need your professional advice once more; I hope you don't mind as I truly appreciate all your efforts/inputs to improve this hobby. 
<thanks again... but it is not entirely altruistic: Bob pays us handsomely in chocolate malt balls>
I have a few questions regarding my recently purchased squamosa clam and maxima clam. First, let me preface by giving you the conditions of my 90 gallon reef tank: lightning--powered by 2x-175 watt 10,000K metal halides and 130 watts of actinic PC, and water parameters--pH @ 8.3, carbonate hardness @ 10.5 dKH, salinity @ 1.025, calcium @ 400ppm, temperature is constant @ 78 degree, magnesium @ 1300ppm, ammonia @ 0ppm, nitrite @ 0ppm, and nitrates @ 2ppm. Fishes included are: yellow and purple tangs, and 3 flame wrasses.
The two clams were purchased 3 days ago and they are both about 3.5 inches. They are placed at the bottom being acclimated to my lightning system. 
<excellent... that was my first question in mind... Good move>
I plan to move the maxima clam towards the middle of the tank at the end of this week and leave the squamosa clam at the bottom. Would this be a wise decision? 
<because of adult sizes and likely light requirements, I would agree that this is reasonable>
My concern with both of these clams is the wide opening of their incurrent siphon. It is more pronounce with the squamosa than the maxima and this occurrence only happens when the metal halides are on.
<many theorizes for this...not all bad. Have you read Daniel Knop's Giant Clams book? Excellent!!!>
When the metal halides are off and only the actinic PCs are on or the lights are completely off, the incurrent siphon is completely closed. Is this normal behavior? 
<the predictability of it is reassuring but categorically it may not happen with all>
Or should I be concern with predation, sickness, and/or accumulated stress from shipping? 
<do examine closely (and periodically 4-6 times yearly or better) for tiny Pyramidellid snails>
I performed the shading test, and the maxima is very responsive to blockage of light and the squamosa is less responsive. 
< an unreliable test. Some like T. gigas hardly respond at all>
This has led me to wonder about the correlation between the squamosa having a wider incurrent siphon opening and its slower response rate to the shading test as not being in good health. 
<not necessarily>
I have also checked for predation with a flashlight at night and I did not see any snails on the mantles. 
<excellent>
I feed DT's twice a week. 
<hmmm... do read in Knop's book about feeding protocols and foodstuffs. Also, review past FAQs and archives on how best to feed such phytoplankton supplements unless you are already using a blender>
Is there anything I do to help them? Any comments and/or input is greatly appreciated.
<unfortunately the clam is not exhibiting any symptom that we may fairly act upon. Your system is very fine, and acclimation procedures quite considerate. It may simply be acclimation/adaptation or even nothing at all. Do not be attempted to move the clams at all for at least 2 weeks. Observe their behavior and follow up here if necessary. I suspect at the end of two weeks there will be no new news <wink> and all will be fine. Best regards, Anthony>
Thank you, Dan

Is my clam doomed
I have recently acquired a 2" derasa clam. He was 10" under 200 watts of Smartlight. Last night he jumped down a step on my live rock, but he left behind some white tissue still attached to the rock above (byssal (sp) tissue?).
<correct>
Is there anything I can do or anything I should look for Thanks Jeremy PS other than this he appears to be in good health
<no worries at all... clams commonly abort old byssal tissue. It is generate new at the new point of attachment. Freshly imported/disturbed clams will often do this. Probably just fine. Make sure it attaches soon for its own good (protection of byssal port from crabs, worms, etc. Anthony>

Derasa Clam problem..
Hello again,
I am writing to you this time about one my Derasa Clams. I have had them both over 1 month and they have been looking fine. Both have been placed on the substrate in the middle of the tank. Today, I noticed that this one in particular, had receded it mantel way back into its shell and the mantle has started to separate from the shell. It does open and close occasionally. The other clam is doing well. I am using 96W PC lights from Custom Sealife(8800k daylight and 6700k actinic). I have plenty of water movement 1 Rio800, 2 Rio 180 and water moment from an AquaClear 300 and HOT magnum (both about 300g.p.h.). Water levels are temp = 76.6, PH = 8.1, Ammonia and Nitrite =0, nitrate = 2.2, dKH = 9.14, Calcium = 490, Phosphate = 0. 
<Mmm, your calcium is a bit high...>
All of my corals Euphyllia sp., leathers and plate corals are thriving. I have read through the FAQ’s section on www.wetwebmedia.com
<http://www.wetwebmedia.com/> and did not see any similar instances of this happening. Am I losing a clam or is there something I can do to save him??
<Even after a month, this specimen may simply be "settling in"... Do take a close look (especially at night with a flashlight) to ascertain whether "somebody" is bothering this clam... worms, snails... can be trouble. Bob Fenner>
Regards,
Keith Broadbent

Re: Derasa Clam problem..
Do you think he may not be getting enough light and to try moving him up higher on the reef??
<Hmm, possibly... worth trying. Bob Fenner>
Regards,
Keith Broadbent

Clam questions
Bob,
Thanks for you response. I have some additional questions though, - You mentioned it might be a lack of light, but I didn't think this was the case because the clams didn't overextend their mantle (as described in Knop's Giant Clams book), and they didn't show any bleaching that I would expect. I also tried a variety of placements in the tank - including placing small maximas/Croceas (1") within 4 inches of the surface. 
<Mmm, the placement is a valid indication, the non-extended mantles, bleaching not necessarily so>
Also, the demise is sudden - the clams usually look healthy for 1 month or more, and then die within a week (usually within 5 days). Am I missing something in regard to light?
<Not likely if the losses were rapid onset... more likely something amiss with chemistry (mis-supplementation in most cases) or an undiscovered parasite load of consequence (like Pyramidellid snails)>
- You asked how I maintain water chem. I use SeaChem's Reef builder and Reef Advantage Calcium. I also use instant ocean salt. (I am in the process of converting one tank to a calcium reactor - Korallin). Is my use of SeaChem's products potentially involved in the demise of my clams?
<Doubtful. No other additions?>
- You discounted my thoughts on predation. The one thing that keeps pointing me in this direction is that I NEVER loose multiple clams at once. It's always one at a time. And then shortly (within 1-2 wks) after one dies, another one starts to show symptoms. Again, can you expand one why you don't think its predation?
<Could be... In accounting for how many specimens lost this is just historically about third, fourth in line as common causes/categories of loss>
- Do you have any idea of what the normal survival rates for maxima/crocea clams are when they are purchased from good mail-order firms (FFExpress, and others):
<Just guesses... such data are rarely recorded, never shared in the trade>
1) the small ones (1" and under)
2) medium (1 - 3")
3) large (3+ inches)
<Hmm, I would state with certainty that "larger ones live longer"... And guess that one inchers on mean/average probably only make it a month, 1-3" probably 2-3 months (most are "killed off"), 3" ones probably 4-6 months... Some folks do keep any/all sizes for years... but most "don't make it">
The reason I ask is I'm trying to get an idea of what constitutes 'Success'.
<My friend this is beyond us! "Smiles per hour"? Reproducing? Closing the loop, having tank bred young grow up, in turn producing viable young? A subjective measure, the affective domain... "how you feel"?>
I haven't had much luck with long term clam survival (except for my large and indestructible derasa), but from what I've seen, the LFS's don't seem to have much luck either.
<Some sources, lines are decidedly much better than others... Much has to do with how these animals are kept, treated "intermediately" going from almost wild culture facilities through holding/shipping... Need TLC at this crucial junction... intense lighting (likely MH), foods, feeding, addition of biomineral, alkaline materials... Only know of three outfits out of dozens that provide this level of care... their clams are healthier, on "average" live longer/better>
- You mentioned phosphates (and Knop indicates nitrates are needed) for clam health. 
<Yes, actually for all life on this planet.>
My kits have always registered 0 phos/nitrate. Should I be 'injecting' phosphates/nitrates into my tank (gosh - this is tough to swallow, given the effort I went to eliminate them).
<Mmm, regularly exogenous (outside, provided) feeding of your livestock should present enough of these... do you have too vigorous "other" transport mechanisms? Like chemical filtration, too much macro-algal growth...?>
I have Red-Sea Berlin classic skimmers running on both 75 gal tanks, with 100+ lbs of Fiji LR and planted/lit sumps. 
<Might try trimming back the macrophytes in the sump>
This combo seems to bring nitrates/phosphates toimmeasurable levels, at least with my test kits (nitrates under 2.5 ppm, phosphates under 0.05 mg/l). I'm sure there are some levels of nitrates/phosphates though, because the macro algae - Caulerpa - in my sump grows well.
- any other suggestions on what I could try to increase my survival rates, or what could be the cause?
Thanks again - and apologies for the long note.
<We will be discussing this... nature further. Bob Fenner>

Clam question
Bob,
I'm back with additional questions. I have 2 75 gallon tanks both with PC (4 55 watt -7100/6700K on one tank and 4 65 watt - 8800K/7100K on the other tank). I'm having problems keeping clams for long periods of time.
(Nitrates, nitrites, ammonia, phosphates are 0, ph 7.9 - 8.4, Calcium is 400-450, alk 9-10, salinity 1.023 - 1.024, oxygen is at saturation, temp 78 - 80).
<Mmm, could be a few things... including a need for more light (or moving the animals up in the water column), foods/feeding of the clams, a lack of phosphate... got to have some>
I've had one derasa clam (4 in shell) that has survived for 2 years now and has always looked like it was thriving and continues to do so - its added 1 - 2 inches in shell growth since I purchased it. I've had a maxima (3 in shell) that thrived for about 8 mo.s, and then suddenly died. I've also had several baby maximas (1in) - roughly a dozen - and around another dozen or so small crocea/maximas/squamosa/derasa (2 in) that have also died.
Basically, they appear to thrive for several weeks, and then they all appear to become ill and die within 1 week:
- initially, they fail to extend their mantle much past the shell edge.
- then they start to show 'gaping' on their inlet siphon. (within 1 -2 days)
- then (within 1-2 days of the 'gaping') they suddenly die. 
<How are you modifying your water chemistry? Doesn't sound like predation, parasitism...>
Usually their is very little flesh left by this time - my reef hermits will consume what's left within 24 hrs. I suspected the hermits, but they seem to ignore the clams until the very last stage - when its obvious that the clam has died. Also, if I have multiple clams in a tank, they never show illness allat once - its always a one by one demise. I've also tried a variety of positioning of the clams (bottom, middle, top) to no avail.
I've suspected a predator, but the shells don't show signs of a boring sponge (or any bore holes from snails). The remaining flesh also appears free of predators. Any ideas what could be causing this - and why my 1 derasa has never shown a day of 'weakness'? 
<A tougher species, individual for aquarium use>
Are small clams inherently more susceptible to illness?
<Yes, more>
I also had a few additional questions:
- are you familiar with the Aqualogic cyclone titanium drop in chillers? 
<Yes, some>
If so, are their titanium coils fairly safe (in terms of poisoning tanks)?
<Yes>
- What is your opinion on the Tunze skimmers and the ETSS skimmers? 
<Tunze products are excellent, though pricey. ETSS skimmers are great technology for very large (hundreds of gallons), "messy" systems, in situations where folks don't mind spending the money on high volume pumping. Needle wheel technology is superior to downdraft. My opinions are posted on the www.WetWebMedia.com skimmer sections>
The Tunze claims to be completely plankton safe (I've heard the ETSS marketed as
plankton friendly). 
<Mmm, the Tunze much more so>
Are these top notch skimmers? 
<Top notch?... for the types of skimmers they are... Tunze particularly for size, cost of operation are very well designed, engineered, built... ETSS are more garage/chop shop put together>
Is their 'plankton' spin true, or just marketing?
<For Tunze more true>
- The ETSS website claims that skimmer throughput (gals of water/hr) is a very good measure of a skimmer's ability. Is this a good measure to compare different brands of skimmers?
<No, ridiculous... what does flow rate have to do with removal of unwanted materials. Removal per kilowatt energy consumed, per pass... these are measures of efficiency. Look at the Euroreef line for a paragon of excellence... their link can be found on WWM. Bob Fenner>
Thanks!

Just lost a Derasa and a Maxima
Hi Bob,
<Yikes, what happened?>
I feel so sad that I just lost two / all of my clams, one Derasa and one Maxima. I have had them for 9 months and a year respectively .. both died within a week apart. I first notice something is wrong when they wouldn't open that much, tried to adjust lighting, but the shrinking continued and then both were in some sort of "gaping" position until I removed them. I noticed they both seem to have lost their legs and that it looked very hollow bottom up.
<Hmm>
I am a little puzzled and very concerned with the clam losses. If you remember, I am in the middle of battling Cyano and looking up my log, I setup a refugium with macro algae and took out the HOT with AC and phosphate sponge 2 weeks ago. Other than that, everything else have remained the same. Do you think they died from poisoning from the macroalgae (there has been no dying though)?
<Doubtful>
Or is there some sort of a "predator"? 
<If they were "hollow" inside it may be so... Pyramidellid snails, some polychaete worms can eat Tridacnid clams quickly in numbers>
I added the Kent buffer to boast alkalinity over the last 2 weeks, from 6.8 to 11.2 then 12.5 over 2 weeks.
<Mmm>
My parameters are: 60G reef, Ph 8.0, NO3 2.5, PO4 <0.03, Alk 12, Ca 400, temp 80-82F, 45lbs LR, 1-2inch sand. Livestock: flame angel, yellow tang, damsel, goby, bubble corral, frogspawn, flowerpot, mushrooms, sun corals (all arranged at a distance from one another), cleaner shrimp, Astrea and hermits.
Thanks.
Brian
<There was nothing left of the clams? Very strange, as in disturbing. Bob Fenner>

Clam Questions!
Hi Bob,
How are you these days! 
<Fine>
I have these weird encounters between my 4.5 inches clam that I bought last week who is moving and getting rid of the poor thing. Anyway! two days after I got the clam he was happy, in fact still is under the metal halide about 9-10 inches below the 175watt MH, lying between 3 rocks. The strange thing I saw was the snail (which I believe a somewhat related or maybe it is a turbo grazer type) (this snail also runs across the algae and suck on them clean), was attached to the clam. I decided to pick the snail and pull him off the side of the clam, man! I had to pull him really hard, which I thought what a good suction! 
<Yes... good designs...>
Today! I went home and saw the snail attached again, I pulled him off and it's even harder to pull this time, but the strange thing I noticed was the hard shell part of the clam had hole as if someone tried to drill a perfect hole. 
<Perhaps "they" did>
I know the darn thing is really hard, and can't imagine the snail would do this kind of thing! I'm afraid that the clam might die from this situation, because a year ago, I used to have 5 of those regular looking (round shape) turbo grazer snail, until I bought this strange looking one which he did the same thing attached to these snails, and died few days later. As a result I have tons of small snails (baby ones). I have 2 theory, 1 good and one bad.
Lets start with the good one first, which is he thinks his trying to mate with his own kind! 
<Nah>
2 his feeding on the clam, but how can that be if the snail feeds on the algae AKA vegetarians type. 
<Things are not always as they seem... this animal may have a wider food preference than you assume>
The mysterious part is how
the heck did he put the hole through the hard shell of the clam?
<A radula, odontophore... specialized structures like a rasping tongue and muscular apparatus for such boring... and secretions to aid in melting the non-living matrix of the shell... There are several groups of invertebrates with species that do this...>
I thought I would go directly to the expert, thank you in advance, hope you have a good one.
RL
<You as well my friend. I would surely remove this snail. Bob Fenner>