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FAQs about Hermit Crabs 2

Related Articles: Hermit Crabs, Crabs, Marine Scavengers Fresh to Brackish Crabs

Related FAQs: Hermit Crabs 1Hermit Crabs 3Hermit ID, Hermit Behavior, Hermit Compatibility, Hermit Selection, Hermit Systems, Hermit Feeding, Hermit Reproduction, Hermit Disease/Health,
By species:
Calcinus laevimanus (Zebra, Left-handed Hermit), Clibanarius tricolor (Blue-Legs), Clibanarius vittatus (a common Gulf of Mexico hermit crab), Dardanus megistos (Shell-Breaking Reef, White-spot, Fuzzy Leg Hermit Crab)Paguristes cadenati (Scarlet, Red-Legged), Petrochirus diogenes (a and other Giant Hermit Crabs), & Anemone Hermits, Sponge/Staghorn/Coral house Hermits, Unknown/Wild-collected,
& Land Hermit Crabs, Squat LobstersMicro-Crustaceans, Amphipods, Copepods, Mysids, Hermit Crabs, Shrimps, Cleaner Shrimps, Banded Coral Shrimp, Mantis Shrimp, Anemone Eating ShrimpMarine Scavengers Crustacean Identification, Crustacean Selection, Crustacean Behavior, Crustacean Compatibility, Crustacean Systems, Crustacean Feeding, Crustacean Disease, Crustacean Reproduction,

More Hermit Stocking Questions >Thanks, again, Marina. >>My pleasure, Barb! >When you say two dozen "animals", are you just talking about the invertebrates (in this case hermit crabs) or are you referring to ALL of the tank inhabitants (i.e., including fish)? >>I am referring SPECIFICALLY to total hermit crabs.  I feel that Steven Pro's assessment of stocking is quite prudent, and you would do well to follow that advice. >Regardless, I bought 10 dwarf red legged hermits today at a LFS (none around here had any dwarf blue leg or dwarf zebra in stock and Live Aquaria charges $25 for s/h) and put them into the main tank after adjusting them to its temperature. >>Salinity is another VERY important parameter to measure and adjust for, as well as pH (this is more for the people who read the FAQs daily). >Unfortunately, my much larger dwarf red leg hunted two of them down and grabbed hold of them (one at a time). >>Ouch!  Son of a GUN!   >No matter how many times I relocated the larger one to high live rock or different areas of the tank, he was relentless...and FAST. >>Arghh!  Is he a candidate for the "derelict tank"?  (These seem to be growing in popularity, and they often seem to do MUCH better than the more dedicated setups!  Go figure.) >Their shells were so much smaller than his, I doubt that housing was the issue here. >>Absolutely agreed.  But, don't tell me he didn't even EAT them. >I decided to put the big bully into the QT (scrubbed clean, new bio-wheel, perfect water conditions due to the use of a good deal of the water from the main tank). He was originally one of four that we purchased early in the year... a murderer who apparently didn't kill for shells, but for sport! Let's see how he likes solitary confinement! >>Oh lord, I bet he DOES like it.. >If your reference to "animals" was just to crabs, then a few more of another species is surely in order, to prevent brawls.  Barb >>Agreed.  Did I mention that I have a friend who buys shells at the craft shops?  She boils them for a while, then just tosses them into the tank.  I know other folks who go scrounging the fish shops and ask for the "dead snail shells", which the shops tend to just give away.  I'm very glad that things are going relatively smoothly (murderous hermit crabs aside, of course).  Marina

More Hermit Questions - Salt System >Thanks, Marina, and Merry Christmas. >>Thank you, Barb.  I hope yours went well. >I haven't had any success in finding quantities of hermit crabs at LFSs, so I'm planning to venture into an online purchase through Live Aquaria. Any concerns? >>This outfit has a very good reputation. >They have a 10-day conditional guarantee where you must quarantine them or they take no responsibility for them. >>This is prudent on everyone's part. >By "drip acclimation", do you mean float the transit bag, add 1/2 cup QT water every 10 minutes or so 4X, then add to the tank? (Live Aquaria suggests 4-minute increments and dumping half of the bagged water after the last 1/2 cup addition, adding tank water, netting the livestock (even inverts) and only adding THEM to the QT, not the bag water. They recommend quarantining for two weeks.) >>Two weeks is rather insufficient, in my own opinion.  A drip acclimation method is one where you actually set up a "drip line", made with a length of airline tubing and a valve to control the drip rate.  You then set up the animals in a container (in the trade usually a flat, but sufficiently deep, plastic pan or box - think cat litter-type box), then create a gravity-fed drip.  There are a couple of ways to do this, one where you'll have to change out part of the water on a regular basis to ensure removal of all shipping water, the other where you have one drip of new system water going in, and one from the acclimation container going out (this will be set up so the drip rates are equal and constant, leaving a constant water level as well).  This is, in my opinion, an safer method of acclimating invertebrates.  However, many folks have neither the materials, money, nor inclination to go to this trouble, in which case the method outlined by LiveAquaria should be fine. >Do you think 12 each of dwarf red tip hermit, dwarf blue leg hermit, and dwarf zebra hermit, and one scarlet reef hermit is too much for the 110 gal tank (holding about 50-60 lbs of rock)? >>Yes, I do think that's rather much.  I'd go with no more than two dozen animals in a system your size, and honestly, since I feel it's easier to add more if necessary (plus, allowing for other animals that would make use of detritus - such as Ophioderma spp. - would give additional leeway), or you may end up needing to feed supplementally. >I was planning to put 24 empty shells in there with them. Better to put in 36 empties? What do you know about the behavior of dwarf zebra hermits?   >>Don't know any particular specifics, you want to give them each at least one extra shell that's just a bit larger than their current digs.  Lots of folks will actually go match shells from craft stores (cheaper!).  Shape is important.. I think I've mentioned this before though, yeah? >P.S. to my reply earlier this evening - My Mithrax doesn't bother anyone/anything in the tank and prefers to hang out underneath things. >>Yes, they do prefer the underhangs. >Even when he does climb, he's very unobtrusive. Overall, a pretty shy little guy who keeps to himself. >>As long as he keeps to himself, it's all good. >The longest I've seen him out and about is when the Tang's seaweed clip falls off the glass on occasion and he runs over to pick the remaining clipped morsels out as a snack.    Post postscript to my first reply this evening - I just read Steven Pro's response to an FAQ on your site regarding quantities of hermit crabs. He recommended no more than 1 hermit per 10 gallons, so it looks like I'm better off just getting another 9. Maybe a mixture of dwarf zebra, dwarf blue, and dwarf red tip (leg). Your thoughts?  Barb >>That number sounds MUCH more like it, and I think an even mix of the three species will reduce quarrels over housing.  Marina

The Chromis Were the Culprits? V - Hermie Question >You're a woman of many talents, Marina. Thanks so much. >>Aw.. shucks, thank you Barb. >The very best holiday wishes to you as well! By the way, everyone is getting along swimmingly (sorry, couldn't resist) in the main tank. >>Am I rubbing off?  I love it.  ;) >No more turf issues either. >>Excellent! >I've got a crab question for you. I currently have one small hermit crab (green legged with red horizontal striping, red antennae) and one nickel-sized emerald green crab. >>Watch out for those Mithrax (emerald) crabs.  They are known to become quite destructive.  However, don't can the crab just yet, but DO watch him.  Plenty of folks have had theirs for years with no problems. >I'd like to get another 20 hermit crabs (110 gal tank), but I want to make sure they're compatible with the other two crabs (and the 1.25" dia Turbo snail). I've read a lot about hermit crabs and it seems that the blue legged and red/white/blue legged species are the most non-aggressive. What is your opinion? >>Agreed, the very slender/delicate types seem to be the most well-behaved in general.  One thing to remember is that any Hermie will quarrel with another if they both want the same flat.  So, do provide plenty of extra shells. >Also, do I need to quarantine the new crabs before dropping them  (and a bunch of empty shells) into the main tank?  Barb >>Most folks would say no, and honestly, I probably wouldn't bother for my own tank.  However, if it were for a customer's tank, I would q/t them.  Kind of like when you take care of other people's kids?  I think you'll be fine, if you're worried about the shells then boil them for 10-15 minutes to make sure they're clean.  Drip acclimation will be best for the hermits, I'm sure you've got THAT bit down by now.  Honestly, I think you and they will be fine, though you might be feeling a little gun shy and want to q/t to be safe.  Marina

- Hermit Crab Lifespan - Hello, would you be able to tell me how long red leg hermit crabs, and blue leg hermit crabs live?  Thanks <I can't say exactly, but do think it's a handful of years - two to three easily. Cheers, J -- >

Hermit shells? - 12/10/03 Hi, <Sorry for the delay> Love your site. <Me too> I check the Daily Q @ A frequently and it is at times as entertaining as informative as something like my 55 G reef tank. <Agreed> Which brings me to why I'm writing. <OK> It is my clean up crew. I purchased a Reef Tune Up Kit from Indo Pacific Sea Farms. <I am thinking of doing the same> This included a dozen Micro hermits (Calcinus sp.?) that seem to be doing quite well. <Good to hear> In fact, at least two of them have grown large enough over the past couple of months to inhabit snail shells about 2.5 mm in diameter. They don't seem to be harming anything and seem quite social. <very cool> In fact, two of the largest stopped to exchange compliments on each others choice of shells just yesterday. <Careful and watch them they could become very aggressive towards each other> I'd like to be a good landlord an make sure that I have a large enough variety of types and sizes to keep them in rentals and not fighting over choice mobile homes. <Agreed. More shells than crabs is a very good idea> Who supplies shell packs that would meet my (their) needs? <I would just go to your LFS and ask for some of the many shells I am sure litter their tanks. Or ask them if they can contact their supplier of inverts for various shell sizes for hermits. I am sure someone can oblige> And just how large might these critters get? <Should stay fairly small. Maybe about inch and a half or less> Should I contemplate a crab dinner somewhere along the line or say, perhaps another, larger, tide pool style tank? <No need> Searching your archives has been unproductive beyond the obvious advice to get larger shells. <Not anymore. Thanks for your question. ~Paul> Regards, Charlie H.

New Tank/Hermit Crabs Hi, I have a new 29 gallon marine setup than has been curing for 5 weeks now. <Wow! Very new to the hobby??? Welcome to a world of wonderment and addiction, mate>  Its a live rock system. I have checked the water for ammonia, nitrite, PH and salinity, all of which turned out fine but just to be on the safe side I also took a sample of the water to my local marine specialist and again it tested fine. <Very good. I always use a few test sources just to calibrate my own findings> So I bought 5 hermits and 4 snails to help clear the tank of the algal growth that had covered the rocks, glass and bottom of the tank. <OK> About 2 hours after I had introduced them I checked on them and 3 of the snails were almost dead on the bottom with the other 2 still on the glass but very weak. <Did you acclimate?? Should do so over a long period of time if you ask me. Sometimes a huge difference in water quality between your tank and the dealers. The process for inverts from a dealer to my tank can take up to 2 hours and even more in extreme cases (starfish)> Also 3 of the hermits were hanging out of their shells looking dead and the others again weren't moving around and looked very ill. <Interesting> I immediately took the hermits out of the tank and they seemed to recover a little in the air. <depending on what hermits may have been necessary. Some hermits work intertidal areas meaning they sometimes need a little air from time to time> The tank has a red algal growth covering the rocks that looks like velvet. <Sounds like Cyano-bacteria. See here: http://www.wetwebmedia.com/bluegralgae.htm > Could this be the problem or is something else causing these animals to die? <It is A problem, but not in the cause of death in your hermits and snails. Check the posted links for more information regarding bacteria-bacteria. As far as cause of death for your inverts I couldn't say. If parameters are all in check, try a longer acclimation time. Make sure you are getting quality livestock by watching the animals making sure they are active and have been in store for awhile. (not a good idea to new arrived shipments from a dealer) Quarantine if possible. -Paul>

Dying hermits - 11/20/03 The only thing I knew about acclimating was to leave the tank in the bag for a while. Though I have just been informed about slowly adding small amounts of tank water into the bag. The hermits are a reef species so I don't know if they require air but they didn't have any in the suppliers tank. <you would be surprised! Many species of hermits require a spot to grab some air. Not all, but again, there are a great many who can take advantage or air. In any event, not "THE" issue here in my opinion.> The animals had been at the dealer at least a week. <Very good. I think the issue here was that your acclimation procedure was improper for these animals. There is likely a disparaging parameter between your reef water and the dealer holding water. Keep that in mind with all your additions -Paul> Oh and thanks for replying. <No problem.>

Hermit Crabs My daughter and I found some hermit crabs off the shore of Biloxi, MS. Can you direct me to a location on how we can care fore these in our home? Thanks    Dave <Hey Dave, I wish I had more info for ya.  I would start with the links below for care sheets and forums on hermit crabs. http://www.landhermitcrabs.com/ http://www.hermit-crabs.com/ I hope it gets you off to the right start.  Best Regards, Gage>

- Legless Hermit - My Dardanus megistos lost all its legs, it can't walk. I have bin trying to feed it by hand. It's about 1 1/2 years old. What should I do?
<You've probably done all that can be done, and I'd continue doing this as long as is practical for you - the legs will likely grow back after a couple of molts. Cheers, J -- >

- Explain This! - My crabs are doing very great and I am very glad of that. <Me too.> But I've had six hermit crabs in my lifetime. <Well, let's both hope that you've got many more years ahead and more crabs to obtain.> Well I first got two Crabby & Kirby. <Wonderful!> Kirby died first. <Oh, that is a bummer.> I was very sad and I cried a lot. He looked not nourished but I kept a close eye on them everyday and checked their water daily. <Hmm... you have a better eye than I do. I'm not sure I would be able to tell a malnourished crab from well-nourished one.> What happened to Kirby? <Honestly, I don't know... these things happen sometimes without explanation.> Sincerely, Crab Lover <Cheers, J -- >

A Carolina Hermie? >We were visiting some relatives on Hilton Head Island and my young son gathered some shells from a beach...he knows never to remove animals from their habitat, but both he and my husband had inspected the shells and thought them to be empty. They were right, except for one shell which has a living crab in it! >>SURPRISE, SURPRISE, SURPRISE!  (That was my best Gomer Pyle impression.) >We discovered this when we arrived at home which is far away from saltwater (Chicago area) and all of the care information I have found relates to land crabs.   >>Alright.  Problem is identifying whether or not this is effectively a land crab or a more committed crab (to the water). >The shell was found out of water originally, and guessing that he(?) prefers a 'intertidal' habitat, we've been giving the crab options of both water & sand. >>This sounds best, as long as you're ensuring it can submerge itself entirely, as well as be able to pull itself onto completely dry land. >We have a friend who is willing to take the crab back to the coast with her, but she won't be going for a while yet, so I was wondering if you could provide any insight as to how to keep this crab healthy... Should the tank ideally be all (salt) water? Can they eat what land crabs eat? >>Ah.. a bit more tricky, but having had young (now teen) sons myself, I'm very sympathetic.  This is what I would do: Keep your setup as described above, but provide a small sponge in a dish with freshwater, just in case it needs to drink fresh water.  As you've learned in your search, even land hermits need to have access to both salt and fresh water.  In this case I would actually use sea salt mix for the saltwater here.  Then, I would provide as a staple those land hermit pellets, with weekly bits of ripe fruit.  If it doesn't take those, or appears to be more committed to the aquatic life, then you can OCCASIONALLY offer bits of fresh shrimp, but be sparing as this will mean more water changes of the aquatic portion of its tank.  Also, as you've learned in your search, the crab may likely require sand deep enough for it to bury itself in (if it's a land crab).  You know the size of the animal, so judge the proper depth based on that.  In the meantime.. have fun with your boy!  Marina >Thank you for your time!

Hermit Crab Hi y'all... Are there any types of hermit crabs one can not put in their tank with corals? A friend went to the ocean on vacation and when they got home discovered one of the shells they picked up still had a tenant and they asked if I wanted it knowing I had a marine tank. I don't want to see the thing die and it's 11 hours to the nearest ocean.<I would not introduce this hermit to your aquarium, especially with corals. Hermit crabs in my opinion tend to be very destructive creatures and are not trustworthy in a reef type setting, Good luck, IanB> Thanks

How many hermits - 10/14/03      I'm a little confused. <Aren't we all?>  On the hermit crabs page, it says: "If you use them, place about one, two small Hermits per actual gallon of your system. <Emphasis on small> Use a mix of species and make sure and provide many "upgrade" homes (empty shells) for your Hermits to move to." <I can agree to this view with the exception that the hermits should be small>      However, on the first hermit crabs FAQ page, the first question reads: "Snail & Hermit Crab waste Hi Bob: My tank finally cycled with a lot of algae bloom. Two days ago I added 10 Scarlet Reef Hermits 10 Turbo/Margarita Snails and 30 Red Leg/Left-Handed Hermits from FFExpress. They have done an excellent job cleaning but I noticed a lot of waste since I added them in the tank. Is this bad for the tank? And should I pull out some of the hermit crabs out? <You neglect to mention how large your tank is. I would not use anymore than 1 hermit crab per 10 gallons. I use about 1 snail per 2-4 gallons depending on the tank, lights, etc.> Thank You, Aram <You are welcome. -Steven Pro>"      So which one is it? <Well, I can see this view as well, different strokes for different folks. Let me tell you what I have in my ten gallon tank. Two hermits. That's right....two. Ask me how many I started with? Ten hermits of varying species. Aggression and starvation has eliminated the competition. So my recommendation is one no more than two per ten gallons period. The same equation works in my twenty gallon for the most part. I now have three left out of twenty. So maybe no more than four in a twenty gallon should suffice>  There's a big difference between one or two hermits per gallon, and one hermit per ten gallons. <Agreed. The above recommendation is what works for me. You might have luck with a few more if you feed them regularly. Is it a little bit more clear? Hopefully so>      As you can see, I am confused. <Naw.......just a difference in point of view. You are gathering information for a better point of view. Good on ya' mate, -Paul>      Brian

Taking from the Sea - 9/28/03 Hello,   We just got home from a trip to the ocean, Bodega Bay area in CA. <Not far from my location> We brought home a small container with some sea water, shoreline gravel, and some kelp. <Cool but why?> I told the kids to go ahead and toss their handful of shells in with it. They wanted to use the shells and sand/gravel later on in their fish tank (after cleaning them). <Not a good idea. Harmful contaminants could be leached regardless of cleaning method> Going through the stuff my kids collected I found a small snail (olive?), <related> some live barnacles on muscles shells and TWO LIVE HERMIT CRABS. <Too bad.> What do I do with these little guys? <Unfortunately, I think watching them die is your only option. They are a mostly cold water intertidal animal. Very difficult to keep without the forethought of study and special equipment and feedings> They are both in snail shells which are appx. 3/4 of an inch. The crabs are olive colored with blue bands on their legs and on their large pincer. <maybe Pagurus samuelis? In any event, It is always a good idea to hold the shells in your open hands for a few minutes (literally) to be sure there is no animal inside. Maybe a digital camera or even quick drawings of things you find on the beach might be a more lasting memory rather than taking some animals homes. (not to mention environmental) Just a thought. I know it is hard to resist. My wife is crazy for shells!> I have a land hermit crab as a pet but I don't know what to do with these guys. <Not much one can do except return them. But a few is really not worth going back to the beach if you live far from it.> They are in a small container right now with the water, shells, kelp and driftwood we found, but I don't know how long I can keep them alive, I won't be able to go back to the ocean for some time so I cannot release them. <Yeah unfortunately, the writing is on the wall> So far they are very lively. <Yeah. Little workers. I too, am fascinated by them. Always foraging and fighting. Fierce little dodgers as well> We have one land hermit crab so I have some hermit crab cakes. I broke one up into small pieces and used a pair of tweezers to hold it near them in the water to see if I would at least have food for them. One snatched the little chunk out of the tweezers as soon as the food hit the water and devoured it. <Always hungry for a handout I tell ya. Hahaha> The other did the same with another piece. Can they live in fresh water? <Nope> They came out of a tidepool and they seem to keep crawling out of the water (probably to get back to the ocean) <yep. They usually are found in varying degrees of salty water and temp. Very durable but fresh water won't cut it.>  and actually seem to prefer to be out of it. <True but they do need it> I am trying to keep the water cool, but not cold. I don't know what temperature they need. <Usually between 58 and 72 because when on the rocky tidal flats (tide pools) they are exposed to varying degrees of environmental manipulation. Such as fresh water addition (via rain), evaporation (via sun) heating (via sun) and cooling (via addition of waters fresh ((rain)) and salty ((during tidal cycles and ambient air cycles)) HELP. <Do your best see what happens. Good luck. -Paul> Michelle

Scarlet Hermit Deaths >Hi, >>Hi. >We are new to this hobby and your website has been a tremendous help!  However, we have a mystery that we can't seem to find an answer for. >>Thank you, you're welcome, and let's see what can be done. >After the tank cycled and the algae bloom subsided, we were left with a few small patches of hair algae and some areas of brown diatom algae.  2 weeks ago, we purchased our first clean-up critters from JEF.  6 tapestry snails and 10 scarlet hermits. 2 scarlet hermits died the second day.  pH and Alkalinity were low (7.8 and 2.1 respectively), so we slowly added Seachem pH buffer.   >>Hhmm... pH is a tricky thing to be messing with.  I wouldn't make changes any larger than .1-.2/day.  The pH is indeed low, but what about specific gravity? >The scarlet hermits have continued to die - one or two every few days.  We left the bodies in the tank, just in case it was molting.  Most of the time they had crawled out of their shells - and their little bodies were still in tact for days (so we assumed it was not a predator).  The really weird thing is that eight of them came to the same area of the tank to die (within inches of each other)!!! >>No answers to that. >We lost the last one today.  He had been really active and was on top of a large rock eating yesterday.  Today, his shell was empty and a 3 inch long bristle worm came out of it.  He is the only one that has apparently died at the other end of the tank (one is still missing).  All six of the tapestry snails seem perfectly fine.  A friend offered to give us a few scarlet cleaner shrimp.  Now we are afraid to take them (don't want to risk their health).  Can you help us figure out what to do?  Also, should be buy a wrasse get rid of the bristle worms? >>No, the worms are there for a reason, and they do perform a function.  If they seem to be of "plague" proportions, you definitely have a nutrient/excess detritus issue.   >Thanks!!!  Dave >The tank is a little over 2 months old - 110 gallon (29 inches tall) with about 85 lbs of live rock and an ecosystem filter (with Caulerpa) sg  1.24 (swing arm tester) >>Poor choice for a measuring tool, in my opinion. temp 80 Alk 4.8 pH  3.0 >>This can't possibly be right, can it?   >nitrites  0 nitrates 0 >>Curious about test kit brand/reliability.  If your specific gravity is indeed spot on, then I am at a bit of a loss, as there is nothing I can think of that would kill only the hermits and nothing else.  I would indeed try the shrimps, one, maybe two, just to see.  Acclimate slowly and watch.  Double check your test kit(s), as well as your hydrometer against something a little more reliable (my own affordable preference are floating hydrometers).  Sorry I can't be of more definitive help at this time, but maybe you'll find something by double checking the kits, etc.  Marina
What is Killing our Scarlet Hermit Crabs?
>Thanks.  We bought a good floating hydrometer.  Salinity is right at 1.024.  Two people have told us that some worms including certain types of bristle worms are dangerous (can kill).   >>Bristle worms will eat what is dead, I doubt very seriously that they are an issue. >We bought an arrow crab that we are very slowly acclimating.  Did we make a mistake?  Also, if we should keep it - do we need to quarantine it (this early in the reef stage)?  Dave >>Personally, I believe in quarantining everything, including inverts.  You've purchased the arrow crab to eat the bristle worms?  If so, consider instead that the bristle worms perform a function, as well as indicate a possible buildup of detritus, as I mentioned previously.  Marina

- Louisiana Hermit Crab ID - I am trying to find out about some hermit crabs my daughter brought home from Grand Isle Louisiana. Their claws are the same size, and legs have a dark color possibly black with a lighter color possible yellow or white running parallel to one another. They look like they stay in the water usually because their shells have barnacles on them. With this information could you tell me what kind of hermit crab these are and how to care for them? <Well, I can't be 100% certain what type of hermit crab they are, but there's a possibility it is Clibanarius vittatus, the Thin stripe Hermit, which seems to be common around the Gulf Coast states. As for care, I think you could likely keep them in typical marine conditions, similar to saltwater fish. You probably wouldn't want to heat the water too much, but ideally match the conditions to those of the waters of the Grand Isle.> Thank you,   the dad that just don't Know <Cheers, J -- >

Hermit crabs in Fiji The other night, here in Fiji,   there were about 2,000 hermit crabs all trooping up from the beach into the woods at the back of the house. I'd really like to know why they were doing this. <Me too... there are "crab aggregations" timed to tides, moonlight... that involve reproduction en masse. Maybe this is one of those? Optimizing chances collectively, decreasing likelihood of annihilation by predation... Bob Fenner>
Re: hermit crabs in Fiji
Thanks for your thoughts. I see that land hermit crabs have to go to the sea to spawn. Maybe these were coming back. Or do they spawn and die? <As far as I'm aware, all spawn and return to land for consecutive years. Bob Fenner>

Electric Orange Hermit Crabs 08/09/03 <Hi Steve, PF with you today.> I searched all over the web and on your WONDERFUL webpage but found no information on what I was looking for.  I have a green hair algae problem right now that I am in the middle of fixing.  At this point I think I just need a few extra cleaners in my tank to finish the job.  I was wondering how you felt about the Electric Orange Hermit Crabs (Aniculus sp.). <Well, after reading on ahead, I'd say stick with the hermits you already have and give it time. One way to remove the hair algae would be to use a dedicated (i.e. don't use it for anything else, ever) toothbrush and lightly scrub the rock during your water change. Use the siphon to vacuum out the algae. Have you looked at your water parameters? It could be a nitrate or phosphate problem causing the growth. The algae needs to get food from somewhere in order to grow.> Am I better off getting scarlet hermits, or is their even a better creature for me to help out with my hair algae?  I have a 29 gallon tank with one flame angel, one percula clown, and one Sleeper Gold Head Goby (not very old).  I might give away the Goby if I don't upgrade to a larger tank within a year. I have 2 scarlet hermits, 2 blue legged hermits, and 2 red legged hermits.  I also have 4 Nerites snails.  So, any suggestions on what hermit (or any other creature) to buy that likes to eat hair algae would be great! Thanks, and keep up the great work on your website. Steve <Test your water first, as I said above, and give your critters time to work, nothing good ever happens fast in a reef tank, in the woods of a very wise friend of mine. Have a good day, and let us know how it turns out. PF>

Coral Eating Crab (8-2-03) Hi, I've just noticed my red-legged crab eating/nibbling on my soft coral. The crab is about the size of Blue-legged hermits, but it's red and has one claw quite bigger than the other. I thought those crabs were reef safe...? :-( <They are supposed to be reef safe.  Watch him some more to make sure he is actually doing damage, then if he is take him out. Cody> Thanks, Luke

-"Hairy" hermit crabs- I just purchased two medium sized (approx 3" shells) "hairy crabs" from my favorite fish store.  These crabs wear shells on their backs like the hermit crab, but the pet store called them "hairy crabs". <Oh, they're hermits all right. Very aggressive though!> I have looked at everything I can find on the internet pertaining to these crabs to no avail. <Likely Dardanus megistos, but impossible to say w/out a picture.> Since I rely on info I obtain from the internet to learn about new purchases I am stumped  by the lack of info on my crabs. <This is one of those times when doing research before your purchase would have been a great idea!> I placed one crab in my 55g reef tank with LR and one coral.  It also has a large yellow tang, 7 assorted damsels, a brittle star and a goby.  Is the crab a danger to any of these already established animals. <To the smaller ones, yes.> The other crab went into a 75g tank with a blue tang (approx 8") and a carpet anemone. <Should be fine in there but the blue tang is much to large for a 75. Please find at least a 6' long home for it, it's a very large fish with large swimming requirements.> I am just stocking this tank as it's only 3 months old.  If these crabs are aggressive I will definitely take them back to the store and get something more compatible for my tanks. <You may be better off bringing them back.> Also since they seem to be of the hermit family should I keep several larger shells available for them to use as homes. <Yes> Thanks for all the info your website brings to those of us who are less than marine biologists. <You're very welcome, but that would include me as well! -Kevin> Janie

Marine Hermit crab reproduction methods - 7/28/03 Hello WWM Crew,<Hello there. Paul Mansur here today> I'm a long time reader and fan of the site. <Fantastic. Glad to hear> This is my first time writing (because the site is so darn comprehensive and all my other questions have been answered before!). I have 2 scarlet reef hermits in my 10g Nano and just want to know if they are hermaphrodites or distinctly male or female. My guess is the former, but their behavior makes me wonder. I think I have seen them mating. They both went down into a big, secluded hole in the live rock and faced each other and sort of interlocked legs and came partially out of their shells so the soft parts were exposed. One crab is much larger and more aggressive and was dominant during this "interaction". The smaller more passive crab is the one I later saw releasing tiny larvae at night (I was shining a flashlight on it). They have spawned a couple times already. I can't seem to find an answer about if they are dioecious or hermaphrodite in my books (I have books by Fenner, Delbeek and Sprung, Tullock, et al). I know this isn't of earth shattering importance, but I was just curious. Thanks in advance! -Ken <Well Ken. I think I have an answer for you but it is based on California species (roughly applies to tropical species as well). This is the answer I personally received today from an associate of mine Dr. Robert Toonen Assistant Research Professor, University of Hawaii at Manoa School of Ocean and Earth Science and Technology, The Hawai'i Institute of Marine Biology I hope this helps. It does correlate with your findings: "There is quite a bit of variability among different hermit crabs in their mating behavior, but I'll try to give you some reasonable generalizations. At least the larvae are relatively easy to raise by comparison to most inverts.  I've never raised any of the popular aquarium species (like blue- or red-legs), but I've raised several of the local CA species.  With one exception, all the hermit crab species with which I am familiar brood their larvae externally (but within the shell) until they complete the nauplius stages (early stage larvae, similar to a baby brine shrimp), this period can vary between about 1 and 12 months, depending on the species.  The females then release either zoea or megalopae (just fancy words for more-and-more mature larval stages) which typically feed on phyto- and zooplankton.  Depending on the species, this planktonic larval stage can last days to months.  Because the youngest stages are brooded within the shell, and because rearing of the later-stage larvae is relatively simple by comparison, hermits are a good choice for an attempt at breeding tank critters at home."          "Hermits have separate sexes with relatively little sexual dimorphism.  The best I can offer is that, in general, the males tend to be larger than the females and in some species the chelipeds (claws) are larger on the males.  Hermits often have elaborate mating behaviors (displays, shell knocking and such) during which the male will guard the female until she releases the prior brood that she is carrying.  Thus, in the aquarium, when people see this, they report a larger hermit "messing" with a smaller one, and suddenly the smaller one sprays out a stream of larvae.  Once the brood is released, the female typically molts prior to copulation (which is why the male guards her) and extruding their next brood.  During copulation, the male attaches dozens to hundreds of spermatophores (packets of sperm) to the "abdomen" of the female, and eggs are fertilized as the female releases them prior to attachment to the "abdomen."  The male then moves on (this "courting" period can take anywhere from several hours to a week or more in some species), and the female then carries a colorful brood of fertilized eggs on her "abdomen" (or more correctly on the pleopods) within the shell for anywhere from several weeks to a year or so, during which time she constantly cleans and ventilates the developing young."          "The larval duration depends on the stage at which the brooded larvae are released.  The larvae typically go through something like 1 prezoeal stage, 4 zoeal stages, 1 megalopal stage and a final decapodid stage of development before becoming a tiny "adult" (although this again varies by species).  In most species, the prezoea and some variable number of zoeal stages are completed while the mother broods the young, until they are released (usually around 2 mm in length) and the planktonic larvae spend something like 20-90 days as a feeding larvae before molting into the decapodid stage (which is capable of both planktonic and benthic life). During this time the larvae feed on phytoplankton but usually prefer small zooplankters (such as rotifers, ciliates and the larvae of other invertebrates) when they can get them.  There are some exceptions in which the larvae are nonfeeding, and spend a relatively short time in the plankton (several days to a week or two), but these cases are relatively rare compared to the number of species that produce the feeding stages, and I don't know of any tropical examples of this off the top of my head. So, if you wanna raise hermits for a reef aquarium, chances are good that you'll have some intermediate- to late stage larvae released by the brooding parent, and will have to feed them until they complete their development...Hope that helps...Rob" By the way, this is from an email to me, Paul Mansur, personally and no reproduction other than the use of it by WetWebMedia is acceptable. Expressed written consent is necessary for its duplication by Rob Toonen. Thanks for your understanding.

Hermit crab hitchhikers: Hydroids - 7/14/03 What's this growing on the hermit crab's shell? Please don't tell me it's Aiptasia. <no worries.. or at least, they are not Aiptasia. They are hydroids... and quite a handsome colony at that. Yet - they can be fiercely stinging and no less formidable to other invertebrates as Aiptasia> I do have 3 Aiptasia in a new tank that I have just begun to stock, but they don't look like this. <no worries about your glass anemones either... they only flourish in tanks with nutrient control problems (poor skimming, poor water flow, overfeeding, etc)> The ones I know that are Aiptasia are0.25-0.5cm across, brown and look just like the pictures on your site. The ones in the attached photo are much smaller, clear and growing like shaggy hair on their transport. Thanks. <do enjoy them in the meantime... a fascinating creature and one that will behave if you maintain proper water quality. Anthony>

My hermits are becoming reclusive!  07/23/03 <Hi Chris, PF here with you tonight> I picked up 9 "zebra hermits" (although I swear they're blue-legged hermits by visual identification) at the LFS for some hair algae control, as well as 4 Astrea snails. For the first few days, the hermits chewed away happily at the algae, and tended to congregate in small meetings. It's been a week, and all the hermits have seemed to crawl into crevices in the LR. They all have their antennae (?) wiggling about on their faces, but they remain in there at leisure. Are these creatures nocturnal? I'm somehow doubting that. I know any aquarium won't live up to what my ideal 'bustling with life' scene might look like, but I was hoping for a little more action out of these guys. Should I be looking towards water quality issues? Everyone deciding to molt simultaneously?  The Astreas seem to be faring well, happily chewing away at the algae. 3 seem to be doing fine. The last one is quite lethargic, moving at a snail's pace, as it were.. I will be doing ammonia/nitrate tests in a few minutes.  pH is hovering at 8.2; s.g. at 1.024; temp ~82F. P.S. Since I last wrote to WWM a couple of months ago, my so-called "hard cure" has long since become quite rewarding, and I could not imagine ever wanting to buy "fully cured" LR! Tons of creatures lurk in the depths of my tank, including strange translucent tentacles (approx 1mm in diameter) that shoot out of tiny holes in the LR and suck in detritus with their vacuum-cleaner like tips (any ideas on what that might be btw)?  Thank you for providing this wonderful service WWM crew!  Enjoying this hobby, even if I am making all the beginner mistakes one at a time, - Chris <Well Chris, they could be blue legs in zebra snail shells. A rose by any other name... As for their behavior, remember, they don't read the same books we do. I've certainly seen my animals doing things that they're not supposed.  The critters on the rocks, are probably some sort of worm, maybe the spaghetti worm, check here for more: http:// www.wetwebmedia.com/polychaetes.htm   Mistakes, well, I try not to make beginner mistakes myself, but all new ones. ; ) At least it was one at a time, and not all at once.  Have a nice night, PF>

Hermit Crab Life Span Hi can you tell me the average life span of a hermit crab please. Steve in England <Hi, Steve.  It depends on the type of hermit crab, land, inter-tidal, marine, etc.  Should be around 5yrs on average, maybe up to 10 for the larger species. -Gage>

Live rock vs. hermit crabs >I have two 55 gallon tank and 45lbs. of Fiji live rock that is curing. In one tank I have 25 blue legged hermit crabs and in the other I have no hermit crabs. If I put half the rock in each tank will it be ok with the hermit crabs? >>I don't see why not. >I know that they are "reef safe" but at one time I had 10lbs. of live rock in the tank with 10 blue legged hermits and they ate the rock to death. The algae and growth was gone. >>Try feeding them directly, especially add a small chunk of shrimp, Nori, or the like (anything that will stay whole while they eat at it).  This should provide enough of a diversion for them.  Do remember to provide them a few extra shells should they get tired of their current "flat". >Also, what is you favorite way to set up a tank? I might be getting a 100 gallons and I'm not sure if I want to go with canister filter, wet/dry, or a good size sump. Thanks for all the help, Andy >>Well, since you're starting from scratch, I suggest looking into utilizing a refugium.  I really love the natural methods of reefkeeping, and a 'fuge is one of the best.  Start on our homepage, look in "marine aquarium articles", then in "set up".  Just TRY shaking a stick at all that's there!  ;)  Best of luck!  Marina

Hermit crabs picking at live coral Hi, I really appreciate all the information I get from your site.   <Thank you for sharing your part today.> I was searching on the necessity of hermit crabs and couldn't find an answer to my question hence this email.  I traded in my 40 gallon tank for a 25 gallon high because I move around at least 3 times a year and wanted something easier and cheaper to maintain.   <Cheaper? Yes, Easier? Not sure about that one as the greater the volume in a system, the greater the stability.> I took my 30 blue legged hermit crabs in as well as all my fish except for the two percula clowns and my fire shrimp.  I have not had any success in keeping my corals alive until I got rid of the hermit crabs, they kept crawling on and picking at them.  I am maintaining a reef tank now and want to add a lot more corals.    <Be careful how you define 'a lot' as with fish, corals need room to grow and feed without having chemical warfare with each other. Do research the different types of corals you are thinking about so you can avoid these problems and choose tankmates that will co-exist with each other.> My question is, am I required to have hermit crabs to control the hair and other algae on the rocks? <Certainly not. Water quality is number one in nuisance algae control. Regular weekly or twice weekly water changes will do wonders. Personally, I don't like the hermits and lean more to a diverse combination of snails. Astrea, Cerith, Trochus, Turbo and Nassarius> I don't think I should get another tang because my tank is too small for one.   <Good call, you don't want fish that are much more than 3-4" when adult. With the 25 I don't think you want more than one more.> What would you suggest? <As per above, Don> Please help!

Little Blue I really enjoy your web site and find it very useful.
<As do I! Ryan helping out today!> Can you house blue legged hermit crabs with red scarlet hermits? I have a 55 gallon reef tank with 75lbs of live rock. The store manager at the place I buy my products says one will eat the other. Is this true? <It's not unheard of, especially when competition for shells is fierce or the scarlet is much bigger.  Many crabs are omnivores in the true sense- they'll eat anything.  Could really go either way. Good luck-Ryan>

Hermit crabs Hello again. <Hi, Don here tonight> I have another question. Can a hermit crab die in it's shell? <I have seen this with red leg hermits I have had.>

Sick marine hermit crab- 6/4/03 Hello Almighty fish-helpers, <Howdy!> I have a common Hermit Crab (yep, the red hairy leg variety).  He (or she?) <depends on how hairy <G>> has been in the family for about 8 months. Up until recently he's been happy in his 75g saltwater fish-only tank. He seems to rule the roost. <they can be rowdy indeed> I've always provided him new shells to check out and he moves into one now and then. The last week he's been hanging out in the corner, not moving much and not as eager to get around the tank.  He eats much less and seems to have the blues. Any thought? Thanks, Steve HJ <perhaps lack of iodine for proper ecdysis/molting. Iodine is critical for it, and yet is only good in solution for hours/days (part of the reason for recommending small weekly water changes instead of monthly or longer). If the tank gets not iodine/reef supplements and/or has been light on water changes, the little bugger could be starving for iodine. When in doubt, do a water change... 25-50% to see if that stimulates it. Also test your water chemistry: has pH strayed low (below 8.3?), is ALK flat (below 8 dKH), etc. Best regards, Anthony>

Crabs We purchased an eclipse system 6 from you and stocked it locally. We purchased two crabs (I assume left-handed hermit crabs) who have one large left claw. Both are relatively small and are in the aquarium with 5 fish. My question is, do we have to feed these crabs anything specific, or do they just clean the tank as a food source? Is two crabs too much for a 6 gallon aquarium? The pet store staff was clueless, but the crabs were so cute we couldn't resist, even without proper care instructions. <Hmm, well they may get a little hungry at times... depending on how much else is being fed to your other livestock... these are "nibblers" that are best kept happy and healthy by having some (cured) live rock in your system> I wish I'd seen your fish express feature before stocking; I've gained more information reading your site than in talking with the pet store staff. Thank you for your help! Linda Saldana >> <And thank you, for writing and your involvement in the hobby. Bob Fenner>

Get a Claw!  5/1/03 My hermit crab's pincher has recently fallen off. You said it was shedding problems. Should it be a concern? What should I do with the pincher? What should I do? Sorry if these questions have already been answered. Bye.<Well as long as you keep the water quality good and see that the little guy has food he should begin to regrow the pincher in no time!  Hope this helps!  Phil>

- Crab Parts - Hi gang, <And hello to you, JasonC here...> I have four red leg crabs in my 30 gallon fish only aquarium. Water is perfect temp is great. But every so often I will see a crab leg floating in the water on lying on the sand. Do they molt or shed legs? <They do molt although it is usually their entire body, and they can also autotomize [self-amputate] a limb if they need to make a fast getaway.> I have not noticed anyone picking at them. <Could be it all went down while the lights were out... I wouldn't be too concerned.> Thanks Christina <Cheers, J -- >

Hermit crabs - algae Dear WWM: If you were to choose 5 species of hermit crab or crabs in general, for routine cleanup of green hair and filamentous algae in my reef tank, which would they be? I intend on having corals and want "reef safe" varieties. I live in Ft. Lauderdale and can collect hermits from the tide pools.  Can I use these?  If so, what species... blue legged, red legged, etc Thanks, Steve < I would do mainly red leg hermits.  Sally Lightfoots are good at eating hair algae also. Cody>

When Good Crabs Go Bad...Live on WWM  3/19/03 Hello!
<Hey!  You got Phil tonight!> My red legged hermit ate my blenny and a snail.
<Oh no.. are you sure.. did you see it happen?>  
I first suspected my fiddler crab, but I read they don't kill fish, because they are herbivores. My question is, How the heck he could have done it (to the blenny) with his little claws (he is 1/2")? He ate the whole thing.
<I doubt that he killed it.  More likely the fish died and the crab(s) ate the remains.  I have seen that happen, but have never seen a crab kill a fish.  It happens but I doubt it in this case.  Good luck and sorry about your loss!> Thanks
<No problem!  Phil>

Faviid eating hermit crab! LPS with a big appetite 3/16/02 Woke up this morning and found that my Faviid had found some dinner. Cant believe that there mouth can open so wide. There goes one of my blue legged crabs. <yikes... cool picture though. Shawn... I'd like to use this picture with your permission in a future presentation or article perhaps. If you would be willing to give your permission, could I trouble you to send the original (full-sized) image to me at readingtrees@yahoo.com and copy it to here as well in case Bob would like to post/use it? If that suits you, please also include your full name as you would like to have it cited for credit (and an address to mail any possible printed copy to). No worries if you cannot share it, my friend. A very cool shot... indeed large zooplankton <G>. Expensive too if it becomes a habit... Ha! Best regards, Anthony>

Hermit crab ? Fixing to buy some hermit crabs and I was wondering if there were any another animals I could put in the aquarium with them.   Thanks! <Are we talking about land or aquatic hermits.  I would only keep land hermits with other hermits.  If we are talking about aquatic hermits there are oceans full of animals that can live with them.  -Gage>

A Crab-Eat-Crab-World? Just a quick question... <Hopefully I have a quick answer! Scott F. with you tonight!> I just put 1 electric blue hermit crab <Calcinus elegans, RMF> into my 55 gallon tank...he is about an inch and a half to two inches long and was told by the local fish store that he was no danger to my several small (1/4 - 1/2 inch long) blue legged hermits. Please let me know if you see a potential problem with this situation. Thanks much, you guys are great. <Well, in my personal experience, I have not had a problem with this species. However, I have noticed periodic cannibalism among various small hermits before. Sometimes, you just don't know for sure until they get together...I'd keep a very close eye on these crabs, and be prepared to intervene if you see someone sizing up his tankmates for a meal! Regards, Scott F>

Hermit Shell fell inside of Open Brain coral Anthony and or Crew, <Whassup> Sorry about using the old e-mail, but I could not get my browser to work for some reason.   <OK> I have just started to read "Book of Coral Propagation" and both this web site, Bob's, and yours books have been very helpful but I have not found anything about this particular problem.  I just noticed after feeding the fish tonight that a hermit shell is inside of my Rose Brain (Trachyphyllia geoffroyi), <Hmmm... minor correction: a Rose Brain is an illegal Atlantic genus of Manicina... you can a regular Open Brain Coral from Indo likely> I sure hope the coral had a nice meal?   <agreed... but more like an appetizer> The hermit crab probably fell from the rock that is close by into the coral if I take my best guess.  My question is should I go ahead an gently try and remove the shell <yes please... it could hurt this LPS in time> or should I let the coral try and push it out?   <perhaps... try fresh figs> I know Anthony I left the door open on that last part LOL. <took a soft pass at it <G>> I have also attached two pictures for your viewing pleasure. <thanks kindly... it is indeed the deepwater (as red) Open Brain from Indonesia likely> Thanks for your help. be Smiling <will do... I'm gassy> TTFN Sean <best regards, Anthony>

Can you guys help me with questions on Australian Aquatic Hermit Crabs?? I live in Sydney and was given some hermits for Xmas I'm pretty sure that they came native from the south coast of Oz.    I'm assuming that they are aquatic 'cause they have not drowned and have been in sea water for about 3 days now. <Likely so> The water on the south coast can be quite cold so I can only assume that I should not be heating the water, they seem happy at the moment ( I can't wait to get home and check on them!!). <Okay. I agree with the temperature issue> I'm after answers on how often to change the water, feeding, should I have a air pump in the tank, how big should the tank be ( the Hermits are up to 2cm, well that's the shell!!  and I have 4 about that size and 1 pretty small baby one, that's a different variety though.    <As large as possible... at least two gallons per animal, with rock work for them to crawl over, maybe out of the water, extra shells to switch out to. Please see here: http://www.wetwebmedia.com/marine/inverts/arthropoda/crabs/hermitcrabs.htm, actually, the linked FAQs beyond> Pls help if possible as I need to get these babies a proper home and I want to get it right the first time.  Even if you know a website that can help me that would be great. Regards Biddy <Be chatting, Bob Fenner>

Cool/coldwater Hermits Thanks Bob. <Cheers mate> One actually died on Friday night, :-(, however they now have a new home!!! At the pet shop he gave me some algae fish pellets for them to eat, however they don't seem to want to go near it, have you got any ideas on what I can/should feed them??  They seem to like bacon, but that dose not seem like a very balanced diet!!    <Save the bacon... do look into bits of fish flesh, any other meaty foods that originate in the sea> Thanks again Bob regards Biddy. <Be chatting. Bob Fenner>

These Crabs Won't Grab! Quick Question: <Go for it!> I bought 10 small (all <1"; most <1/2") hermit crabs at my LFS to help clear diatoms & detritus from the substrate of my 80G FOWLR. Before putting them in my tank, I became concerned that they could pose a threat to my yellow-headed Jawfish and my Firefish. I haven't put them in yet. Is there any actual cause for concern? Thanks, Steve. <Well, Steve, if they are indeed the "herbivorous" varieties that are commonly used for algae control/scavenging, I wouldn't worry too much. Some people implicate them in coral munching, etc., but I think that most of the "damage" they do to corals (if they do any) is a result of them "walking" over the corals. Most of these guys stay really small, and are quite content to scavenge what they can. I have a number of these in my reef tank (which has several bottom dwelling blennies), and I've never had any sort of problems. Now, that's no guarantee that yours will be perfect citizens, but I'd feel comfortable with them. Good luck! regards, Scott F.>

Urchin & Crab Hey guys- I got a fairly large red hermit crab, has black hairs, white spots and fits in a large Mexican turbo snail shell. my question is, I picked up a small "orange eyed" black urchin, and it looked like the crab was going after him last night. this morning I can't find the urchin, but did see about 10 spine clippings in the sand were the hermit crab was. Are crabs natural <Many are> Is it possible that the crab killed the urchin, or is it more likely the urchin is hiding? <You can look about...> should I remove the crab? (the crab is ill tempered, eats all the snails and what not). Thanks for all the help, Justin <If you intend to have such animals... Bob Fenner>

- Healing Hermit - Hi there, <Hi, JasonC here...> I have a red legged Hermit crab which I am really worried about. He did he usual hiding before shedding. Disappeared into his nice little cave I made for him. He shed his skin late Friday night. I noticed he was hiding inside his shell on Sat. He usually remains grumpy for about a week after shedding. However on Sun he came out of his shell and was missing his big pincher and all his legs down the left side. I don't know if one of the fish pulled him while he was weak or if he just decided it was a good time to loose his shell. <Dropping a limb is an ability crabs and lobsters have that allows them to get away while leaving something behind to distract/appease the predator.> I left him in the tank to reduce his stress however I noticed that some of the fish were bothering him. So I moved him into the sump. He seems to be fine and he is eating etc. I have knocked the calcium level a bit higher to give him more calcium to recover. Don't know if this will help. Is there anything that I can do to help him heal faster. <Not really, you did the best thing by removing the crab to a quiet place to stave off aggression. The limbs will grow back with successive molts. No worries.> Thanks, Rob. <Cheers, J -- >

Mystery Crab Muncher... Hey Folks: <Hi there! Scott F. here!> This morning I woke to find my Red Reef Hermit Crab eaten.  I can tell from the empty shell and his leftover claws on the substrate (looks like the rest of him was ripped away - very sad). <Sad to hear that> I have a 12-week setup of 55gal FOWLR,(1) three-spot Domino, (1) Four-stripe Humbug, (1) Blue Devil, and (1) Goldbelly (all damsels).  I recently added the (1)  Hermit, (1) Emerald Crab and (2) Astrea snails.  I have not noticed any unusual behavior between inhabitants with the lights on.  Are they all suspects? <Possibly- damsels can be pugnacious, but generally will not harm crabs, in my experience. This does not mean that they CAN'T attack crabs, however...> Aside from that, I have noticed inside the LR some skinny white crusty tubes have been built, and worms or tentacles (of hair thickness) move in and out or them.  Any idea? Thanks, Rich <I wouldn't worry about those "worms", Rich. These animals are a normal part of the reef environment, and many cast their mucus nets to filter feed materials from the water column. Keep observing your tank carefully, and look beyond the obvious for your perpetrator! Good luck!>

Re: hermit crabs Kind Sirs, I'm writing to inquire some morning hermit crab activity. It seems the one opening of one shell is inside the other opening of the other shell on the top of a piece of live rock. (one shell is on top of the other shell). They where both acquired at the same time and relocated to larger shells. One shell is about 3/8" and the other is a ?". Not sure if I should ban the children from looking into the tank or if the smaller one is trying to acquire a larger home? There doesn't seem any movement from either shell, which leads to believe they are not fighting? I found them like this, this morning and where still in the same position when I left for work, about 3 hours later. <Hmmm, likely fighting over shells rather than the reproduction lesson, also possibly food.> Yesterday I notice a few were moving around the bottom more actively instead of scavenging. Should I break them up? <No, they will soon be back together.> Or listen for the pitter-patter of little (many) feet.? If so how long would it take for little ones? <or fewer feet...> A side question regarding the new book (Reef Invertebrate): I've been reading and researching many topics in your site prior too moving up to a 75 gal next June. Many question regarding the brothers Kalk and Alk and was wondering if this is touched on in the new book? And the proper way to mix a Kalk slurry? It was referenced many times in the FAQ's that it's covered in Anthony's book "Coral Propagation", and I was wondering (hoping) it was covered in the new book? If not, I'll have to pick up Coral Propagation sooner than expected. Don't plan on adding any coral, etc, until the end of next year. Figure I had some time. Many thanks out to the crew for all of your help.  DaveK <Well Dave, Anthony simply suggests dosing Kalkwasser in a slurry dosed to not raise the pH more than .2 or for example, from 8.2 to 8.4 pH, or until the calcium demand is met in that portion. He suggests starting with 1/16th a teaspoon per 100 gallons of system volume in a cup of cold water and using a digital pH meter to monitor the pH response.  I highly recommend his book for Christmas!  Happy Holidays, Craig>

Do crabs and snails need air? Do regular or hermit crabs require air, or can they stay fully submerged in water all the time? <There is more than one kind of hermit crab...some are mostly land based and need lots of air while others are ocean dwellers that can do fine without air. The ones like pet stores sell in the little terrariums need air and will die if fully submerged all the time> Snails? <The same can be said for snails...>

Cleaning Crew Hello WWM crew. <Scott F. on the WWM "cleanup crew" tonight> I'm currently looking into getting a cleaning crew for my 180 gallon aquarium that consists of 200 lbs of live rock and 300 lbs of sugar size aragonite and wanted to see what you recommended in terms of crabs and snails, I've been hearing some negative things regarding the blue legged hermit crabs and Astrea snails. Thanks, Jose <Well, there are many possibilities here. I have, and still do, use the supposedly "reef safe" crabs without incident. However, keep in mind that even the "safe" species are, to a certain extent, predatory. They can and do occasionally nibble on your desirable corals, and sometimes, your snails! A lot of times, the "bad guy" types of crabs sneak into your tank by using the same shells as the "good guys" inhabit. This may be why a lot of people give a "bad rap" to the supposedly "reef safe" hermits (and another reason to quarantine/inspect all new arrivals!)! I have had great luck with Trochus, Strombus, Turbo, and Nerites snails myself, and would definitely recommend them as part of your "crew". Also, brittle stars (almost all of them) make great scavengers and detritivores, and you can stock them at the rate of about 1 for every 20 gallons. Just use common sense when selecting your cleanup "crew", and you should be okay. Many retailers offer "packages" of these animals, so you should have no trouble locating them. Have fun and good luck!>

Scarlet reef hermit Bob, I have been using the website to help me with a lot of questions, its great! My question is, Do Scarlet reef hermit crabs molt their hard bodies, I know they switch shells when they grow out of their current ones, however this morning when I looked into the tank I saw what looked to be the body of one without the shell laying on the Live rock is this common and nothing to be alarmed about or do I need to go on a mission to find the killer? <All crustaceans, including the Hermits undergo ecdysis (molting) to allow for (generally positive) growth... and often leave their old exoskeletons about (better to leave in the tank as the old owner may ingest/incorporate the matter into its new one... and it won't pollute your system).> Thanks as always, Mike <The next few days after molting are dangerous for the "soft bodied Hermit"... don't disturb the landscape if you can avoid it. Bob Fenner>
Re: scarlet reef hermit
Bob, Thanks for the ultra fast reply!!!!! One last Question what does the molted exoskeleton look like?  <Initially, like an exact model of the original... sans the insides... eventually, just bits and pieces...> I'll try to describe it the best I can. The legs are red, and look exactly like the legs on a living crab, same red color/length, the abdomen looks pale white, almost a milky color and seems to wave in the current freely, it appears it has those small legs use to move in and out of the shell, however its not too large in size, but then either was the hermit to start, and its laying upside down. I don't know how greatly this will help but I'm so concerned for in the case its dead, ill need to make sure its not something in the tank killing them. <Might be a molt... with some of the mineral and matrix content going... Not to worry. Bob Fenner> thanks, mike

Taken from the Sea (LR, sand stars, hermits...) Hi Mr. Steven Pro, Have you been in the Philippines? <No> I've just been on a rocky beach here in the Philippines in Batangas and I took some live rocks. <Insert standard disclaimer: we at WetWebMedia encourage all our readers to follow the local laws, blah, blah, blah...> I would like to know how long would it take to cure my live rocks taken from the sea before I can transfer it to my main tank? <No knowing, when ammonia and nitrite are both zero you are ok.> I took 5 pieces of live rock and it is covered with about 60% purple coralline algae and other life forms. It does not stink but it smells like a rock from the sea (hehe of course that's where it came from). If it does not stink do I still need to cure it? <Yes> Also in its very shallow waters there are numerous numbers of Sand sifting star, they are so many and beautiful and free! I really want to get some for my tank but I don't know if it can live on my bottom gravel since it is not fine sand so I didn't take any for now. Can it live on my bottom gravel even if it is not as fine as the sand what it was used too? <I have seen them kept in what I would describe as coarse sand, but not crushed coral gravel.> What does it eat? <Read here http://www.wetwebmedia.com/seastars.htm following on through the FAQ files.> Will they eat my crocea clams? <No> How many would you recommend for a 75 gallon tank? <No more than one.> On the shore I took some hermit crabs, small ones about ? in. But I don't know if they are reef safe. <Me neither.> Since they are living on the near shore where there aren't any corals I concluded that they would not eat any corals or other invertebrates found in deeper waters. But I could not see these hermit crabs on your crabs site. Only two of them are there and are not reef safe. The rest have black legs with gold spots with red (maybe maroon) antennae and two blue little antennae. Are they reef safe too? <One of Anthony's favorite saying is, "Nothing that lives on a reef is reef-safe. They don't order take out. They all have to eat something. It is just a matter of whether we value what they eat."> With Astreas and other invertebrates (corals, anemone, fishes cleaner and banded coral shrimp)? <All crabs are opportunistic omnivores. They will eat anything they come across that they can eat easily. If food is plentiful, they may leave your snails alone. If you practice good husbandry and do not have nuisance algae and uneaten food everywhere, your crabs will become hungry and resort to other prey items.> Could you identify (from my previous description of its appearance)? <No> When I was looking for live rocks, I saw one which has a beautiful shape and covered with coralline I noticed that there is a small banded coral shrimp there. I wanted to take the rock and the shrimp, but I already have a banded coral shrimp which when I add another shrimp of the same species they may fight. <Agreed> So I just returned it the live rock which was its home back together with the shrimp and just let it be as it was and find another rock. I did not know that these shrimps also live in very shallow waters about only 3 feet deep. I really want to return there and get some additional rocks and some invertebrates. And they are free! <Again, look into the local laws protecting the wildlife before you find yourself in a Pilipino jail.> But lots of quarantine, curing and acclimation, but I don't mind. (I will limit on what I take on the wild since I don't really want to damage anything in it). <Agreed> Thanks, Ken Ryan <You are welcome. -Steven Pro>
Re: Taken from the Sea (Hermits, the P.I.)
So all hermit crabs may not be reef safe unless fed properly? <And even then no guarantees.> Sorry, I forgot to write here that the rocky beach is not really a restricted/conservation area. It is actually like a rock farm. Villagers also take care of these rocks and sell them to different LFS here in the Philippines. There is a small LFS there that sell fishes, corals, invertebrates, and live rock. If you don't want to have the trouble of collecting rocks you can buy it there. But if you want free just get your own for free and they don't mind. <I would double check the laws just to be safe. It would be unusual for any government not to have some sort of regulation in place.> LFS owner also told me that they also export marine life to different countries. You guys at WetWebMedia should come here sometime. <I am sure Bob has been there and some of us maybe in the future.> The Philippines has great reefs in its waters. Very beautiful. Thanks again, Ryan <You are welcome. -Steven Pro>

Hermit Crab Hello those who couldn't make it to MACNA... <<Hey, don't rub it in!>> One of my (saltwater) hermit crabs was upside down in his shell looks for something like a few days and now his claws are missing!!! It looks like he only has two legs right now and is definitely unable to move with his huge shell (he got greedy in getting a new home). What should I do with him until he can grow he claws back, which I am assuming will take a few molts at least? Would it be better if I keep him in the main tank, the sump/refugium <<Perfect!>>, or quarantine tank?? How should I feed him, or at least he has access to food?? <<If your refugium is established and active, there should be plenty there to help a crippled hermit crab to recover... Cheers, Zo>> Thanks, Kim

Red Slime Algae Hi Bob, Haven't written in quite some time. I have a case of Red Slime Algae. I've neglected my tank over the summer (I've been a bad boy) and now I'm going to remedy it through large water changes every week. I know what needs to be done, but I've seen claims from a few "sellers" that Red Leg Hermits eat red slime algae. Have you ever seen this? <highly unlikely... it is a noxious Cyanobacteria disdained by most and fatal to some. Aggressive protein skimming can also eliminate this problem in mere weeks. Seek to get daily dark skimmate from your protein skimmer.> Thanks, Tony <best regards, Anthony>

Staghorn Hermit Crab & Florescent Starfish Hi, <<Hi - JasonC here at your service...>> I am new to Marine Aquarium Keeping. I have a 55 gallon reef tank that in a little over a month old, I set it up using the GARF Bullet Proof Tank Method. It has 2 40watt Blue Moon and 2 40watt Triton florescent bulbs. Anyway, I ordered some starfish on the net and had lots of problems with getting them. So as a bonus to make me happy they are sending me a Florescent Starfish and a Staghorn Hermit Crab. <<Well... I couldn't find any information about a Fluorescent Starfish... you might want to peruse this page and see if you find it under a different name: http://www.wetwebmedia.com/seastars.htm >> I know nothing about the care of these two animals and can find little about them on the net. Could you tell me anything about there care (IE: lighting, food, current, supplements, compatibility etc.). I'm especially worried about trying to keep the Staghorn Coral (that the crab lives in alive) will the lighting on my tank be enough to keep the coral alive? <<In the long haul, I don't think so.>> I have a large Goniopora, and 15 assorted soft coral fragments (from GARF) that are all doing quite well. <<That Goniopora probably won't last long under this lighting for very long - success with this particular coral eludes even the experts and seems to do well only in lagoon/green water type systems. The others will likely be fine.>> But I have read that stony corals need more light and an older more mature reef tank to survive. <<That is absolutely the case.>> Any help with the care of the above mentioned animals would be much appreciated. (By the way I can't spell worth diddly) <<Neither can I - I use spelling checkers like they were tissue paper. But back to your Staghorn hermit - these are "supposed" to be something between a detritivore and a herbivore. Personally, I don't really trust crabs of any type, but these seem to be pretty reef friendly. Your largest concern would be keeping the coral hat healthy, and coincidentally it isn't actually an Acroporid Staghorn, but more Hydrozoan or Bryozoan in nature - much less demanding of intense lighting. I would just continue your normal feeding regimen and all will likely be fine.>> I also have a question about a hitchhiker that is in my tank. It looks like a tiny crawfish about 1/2 to 3/4 inch long, it is a light grayish color with long whiskers and claws about the same size as my Mexican red leg hermits, they are the same color as the body with yellow on the tips of the claws. <<Sounds more like a baby lobster of some variety.>> It has made tunnels all under my live rock with little opening here and there that he covers with little piles of gravel, he has different exits opened on different days and I have only seen him venture out of his caves once, and then he only came out the length of his body and only for a second. He is interesting to watch when I can figure out which hole he is by, he is constantly rebuilding the hills in front of his exits, usually all you see is an occasional claw or whisker and lots of little pieces of gravel being piled up in front of the holes he's made. Any idea what this curious little creature is, or what It's care needs and reef compatibility might be? <<Again, just stick with the normal plan, no extra care necessary - if this is a lobster, it will fend for itself.>> I don't think he's any threat right now since he's so small (other than maybe toppling my liverock with all of his tunnels), but when he gets bigger I'm worried he may want to eat some of my reef inhabitants that I don't wish to have used as food. <<I was going to say that, but you may well have to catch and get rid of this fella at some point in the near future. Sounds like no worries for now.>> Thanks in advance for your help Terri <<Cheers, J -- >>

Hermit crab with anemones Hi Folks - fantastic site,  <cheers and thank you!> I've been loitering around here for a couple of months digesting all the info I can - now I have a couple of questions I hope you can help me with.... I have a huge hermit crab (around 2'" long) with two anemones on his shell. I have two questions.... what type of anemones are these likely to be?  <an excerpt: Dardanus sp., a Coral Hermit Crab. This fascinating species is renown for adorning its shell with living anemones (some with Calliactis species). The anemones serve an apparently clever purpose of defense with their stinging tentacles for the traveling hermit. Said anemones are carefully transferred when the hermit changes shells. The many perils in the confines of an aquarium (unnaturally repetitive and close brushes with other cnidarians, filter intakes, etcetera) make the anemones on the shell of this hermit crab inappropriate for all but a species tank. Not recommended for the casual marine aquarist.> They seem extremely hardy - getting buried in sand, squashed between the shell and the aquarium glass, and scraped along the rock whenever the crab crawls into one of the caves.  <to some extent yes... but in the 6-12 month picture at best... not the long run or natural lifespan of this relationship> I've had this combo for 3 months now, and the anemones are looking very healthy and growing at a pretty fast rate. <please to consider moving the crab and guest to a dedicated and more open/spacious tank like a refugium> Second question - my crab has changed shells 3 or 4 times since I've had him, and he always takes the anemones with him, I've never seen this happen but I'd love to know how this occurs. Does the crab move them over to the new shell, or does he just sit there and wait for them to move themselves? <it moves them> Any answers or more information on this curious combination would be greatly appreciated. <best regards, Anthony>

Coral hermit I just bought a Staghorn hermit crab... not sure just what to call him. <<How about Manucomplanus varians - is a guess really, but is the name of one of the decorator hermits.>> He mostly just sits about the tank watching the world go by. I would like to know if I am supposed to provide future homes for him... is he nocturnal? <<hmmm... well, you do now also need to provide good conditions for the coral he's living in.>> (He sits in the cave that belongs to the shrimp... it takes up about 1/4 of my 60 gal.) I have great water quality, and nothing that would bother him as all other hermits are smaller, and the fish are "peaceful" and small. Any other info on care and behavior would be great, as I noticed this crab is missing in your articles. <<They are fairly uncommon... but I do believe relatively easy to care for like other hermit crabs. You might want to consider removing other crabs for as a batch, they are mostly not trustworthy... wouldn't want one to toss your hermit from its Staghorn.>> thanks a lot <<Cheers, J -- >>

Hermit Crabs I live on the coast of North Carolina and have recently discovered many hermit crabs on the beach. I have been unlucky in being able to determine what species of hermit crabs these are, and cannot find any website regarding native hermit crab species here in NC. <Your best bet is to contact a local public aquarium or go to the library searching for books on native animals.> From what I have gathered, there are aquatic and land hermit crabs. <Correct> I would imagine that these are aquatic types, but my 9 year old insists that they are Ecuadorian Hermit Crabs because he has seen them on the internet somewhere. Do you have any ideas of what types live out here and would wash up on the beach? <No, not really, just that they are temperate species, need cold water and if indeed are aquatic, they will perish in a room temperature tank.> The crabs are brownish in color and have equal sized claws, rather small compared to the purchased hermit crab claws I remember from when I was a kid. Thank you for any information you can provide me. <See notes above. -Steven Pro>

Hermit Crabs & Exoskeletons Hello Mr. Fenner, or who ever happens to be handling questions today. I purchased 6 blue leg hermit crabs about a month ago, and today found what I believe to be two molted exoskeletons and everything I've read refers to them as such, but always prefaced with 'probably'. A quick count of moving shells re-affirmed that there were no dead crabs, however, is there any solid way to tell the difference between an exoskeleton and a dead crab asides from this slow method? Thanks for your help, Josh <Mmm, the only way that comes to mind is to take out the "shell" and give it a squeeze, investigate it under a microscope... cast off exoskeletons are notably very thin... and should be tossed back in... as the moltees as it were, will reincorporate the minerals from their old external skeletons to make the new. Bob Fenner>

Help!!! Hermit crabs I need some advice. My co-worker brought back some hermit crabs as a gift that he found on a beach in Gulfport. He brought them as a gag  <well intended as they might have been... it is a shame that some of us have been conditioned to take life and living creatures with such indifference> but I was dead serious about taking care of them.  <God bless you> I filled an aquarium with sand and plants and did the whole sponge and pellet thing since he said they were land critters.  <very wise and important distinction. Crabs occupy so many different aquatic niches. Dry, submerged, immersed, etc> They weren't moving and a couple actually died. I had no idea what to do.  <they need to be sprayed with water daily... keeps them breathing easy (need moisture for "lungs"... heehee, O2 uptake)> My husband said they were probably sick and suffering and to put them in water and let them die in water as they were meant to.  <they would drown/die if left in water likely> Turned out once in water they stared walking around, swapping shells, etc... I put them in a bucket when I saw they were all alive and watched them. <yes! they just need sprayed/dunked daily but not submerged indefinitely> They are obviously aquatic crabs, They have hairy striped legs and are pretty aggressive to each other.  <natural> What the heck do I do now? I have no idea. Please help me with anything you can. I live in Arizona. I could always take them to California. I'd appreciate anything you could tell me!!! Barbara <bless your heart for your empathy. These crabs are rather easy to care for if you like. They eat most anything. The pelleted foods are fine with supplements of small bits of greens/vegetable matter (not too much...fouling). Again, a spray or dunk daily. Many extra shells to play with /swap. Plenty of branches/twigs to climb. And a shallow dish of water (not deep enough to drown in) for rinsing sand and humidity. Do a key word search on Google for expanded husbandry tips. Best regards, Anthony>

Hermit Crabs My youngest son wants to raise an aquatic hermit crab that he found recently in the Gulf of Mexico near Gulf Shores, Alabama. Can you give me any good tips on how to get him started (e.g., what size aquarium, what type of sand, what type of food, care tips, etc.)? <Do take a look here http://www.wetwebmedia.com/marine/inverts/arthropoda/crabs/hermitcrabs.htm and follow on through the FAQ file, blue link at top of page. Also, try to identify this animal, as some need to get out of the water to survive. Your local library or public aquarium maybe of some assistance with the local animals.> Any help would be appreciated. <Have a nice day. -Steven Pro>

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