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FAQs about Hermit Crab Systems

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

Related FAQs: Hermit Crabs 1Hermit Crabs 2, Hermit Crabs 3, Hermit ID, Hermit Behavior, Hermit Compatibility, Hermit Selection, Hermit Systems, Hermit Feeding, Hermit Reproduction, Hermit Disease/Health,
FAQs: 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,

Be aware that Hermits can/do fall into Cnidarians... to be consumed. Mich's correct ID of a Pseudocorynactis, pic sent in by querior Jim.


Hermit crab salt water.      8/21/16
I've noticed that when I mix the hermit crab salt water conditioner I end up wasting water making it.
Can I mix up the ingredients for the salt water and put it in a clean bottle so I don't waste it?
<Yes. Bob Fenner>
Re: Hermit crab salt water.

Thanks. Just making sure.
<Welcome. BobF>

Re: Hermit crabs  6/19/12
Hi there again, I read the article you sent and since it looks like they can't live in the same habitat could I put the water dwelling hermit in a small salt water aquarium by itself.
 I have a 2 gallon aquarium and thought about putting him in there but don't know if he can live under water all the time.
<Many species can>
 Thank you in advance I'm just trying to save him if possible for my son
<Life to you. BobF>

Hermit crab question, possible pH issue? 1/23/12
Greetings to the WWM group,
<Hello Tom>
 I just recently found your resources online. They have been bookmarked and I have been reading them voraciously. The daily FAQ is an amazing resource.
I am relatively new to the hobby but have always been interested and starting an aquarium has always been on my life's list of things to do. We have a six week old 55 gallon marine aquarium with a ~10 gallon sump system. The sump is gravity fed and the return is a 750 gph pump. The tank started with about two inches of crushed coral substrate and 40lbs of mixed live/base rock. We had a raised shelf of egg crate, hidden in the substrate that the live rock was arranged upon, to promote stability and expose more of the surface of the live rock. We waited for the nitrogen cycle to complete. The diatoms had gotten pretty thick and the green algae was also thriving. Water tests (pH, nitrates, ammonia and nitrites) every 3-4 days confirmed the progress of the nitrogen cycle and its completion about three weeks in. At that point we added a Clean Up Crew recommended by reefcleaners.com, about 110 various snails,
<Too many snails in that size tank, most will starve to death without supplemental feeding.>
a ruby Mithrax and two "Halloween Hermits" (family Diogenidae). They did an amazing job in about 10 days, the diatoms were brought way down, the glass was clean, the hair algae was completely gone and the green algae had been lessened considerably. The snails seemed happy, the hermits were moving about and the Mithrax never stopped eating. Water tests were still acceptable, the ammonia and nitrites spiked a bit when the snails and crabs were added, but within three days went back to zero and then three days later the nitrates were also back to zero. We were pretty excited and thought it was time to add some fish. We found a Tiger Pistol Shrimp and green Watchman Goby (1"-1.5") that seemed perfect and they were acclimated and added. Water tests two days later showed no appreciable difference. At that point we found a Vlamingi Tang (3"-3.5") with an amazing temperament that seemed perfect for our budding tank.
<This fish will get too large for your system.>
We also got a couple of Peppermint Shrimp to help out with some of the red algae on the rocks and substrate.
<Mmm, mainly a carnivore, will do little for algae clean up.>
The water tests the following day did show a small ammonia/nitrite spike (probably coming from the new specimens and the food (chilled copepod mix and pellets)). But that evened out two days later. We had never seen the pistol shrimp after it was added. It dug itself under one of the rocks (also under the egg crate) and seemed happy not being social, which (as I understand it) some shrimp species are wont to do.
<Pistol Shrimp are shy and rarely expose their entire body during the day.>
 However, it was tunneling under the egg crate exposing it and the bottom of the tank which isn't very appealing to the eye. We spoke to a couple of owners of LFSs and they recommended just getting rid of the egg crate.
Since we didn't have any wildlife yet that are position sensitive (like anemones or corals) no one thought it would be a big deal. We performed a water test to make sure we wouldn't be adding to an already stressful environment, pH was 8.0 - 8.2 and the ammonia/nitrite/nitrate levels were all zero. We turned the pump off, made sure all of the critters were accounted for, rearranged the rock and got rid of the egg crate. Stirring the substrate to get the egg crate out caused a massive amount of suspended particles in the water. We were a little worried but with the cycle rate, it was cleared in about three hours. Water tests the following morning showed a bit of a drop in pH, 8.0 and very small rises in nitrates/nitrites/ammonia. We did a 10% water change to hopefully lessen the stress and allow everyone to adjust to the new environment more easily without the added stress of poor water quality. Since that change, the goby and the tang are more active. The Mithrax seems right as rain. The pistol shrimp has found a new home (with the goby! one of the peppermint shrimp seems to have called that burrow home as well) and comes out at night to scavenge, which it wasn't doing before. But the Halloween Hermits have been sluggish, they don't seem to be eating or moving around much.
<Likely preparing to molt.>
This was Wednesday 1/17/2012. We woke up this morning to a freshly shed peppermint shrimp husk (which is great news, they won't shed under stress, right?)
<Is a normal growing process, they must molt.>
but one of the hermits was not in his shell and floating, with the majority of his body gone, apparently eaten. His shell was in the same spot from last night, dug into one of the front corners of the tank. I apologize for all of the information, but reading the "How to submit a question" pages I want to make sure you have as much information as I can provide.
<Ah, one of the few that actually read how to submit.>
 I did that to ask the questions, Did we make too many changes in too small of a window and cause stress to the hermit crabs?
<Unlikely, Hermit Crabs are very hardy.>
Is the pH the culprit?
<No, you are well within acceptable levels.>
 If it were just one of them that was acting strangely we wouldn't be as worried as we are. I can't thank you enough for your time and effort.
<You're welcome.  James (Salty Dog)>
Tom Voulieris

Crabitat   3/27/11
Do my hermit crabs (Clibanarius vittatus) need live rocks or will any kind of rocks work?
Thanks for your help,
Bri :)
<A bit of live rock would be very helpful... on several counts. Bob Fenner>

Stocking around Clibanarius vittatus -- 9/27/10
Hi, WWM crew!
<Hi Jeff, Lynn here today!>
This past April my neighbor gave me two hermit crabs (C. vittatus) that she accidentally brought home from a trip to Florida.
<It happens. These hermits can survive out of water for several days, so it's not all that unusual for a shell collector to accidentally bring one home. One thing of note regarding this species is that they can get fairly large.>
I happily took them, and quickly set up a 5 gallon acrylic hexagonal tank for them,
<Heeeee! Remember in the movie Jaws when Chief Brody told Quint 'You're going to need a bigger boat.'? Well, you're going to need a bigger tank!>
..complete with sand and a couple pieces of live rock (I'm hoping to get more soon). The tank also has a number of majano anemones that I purposely added to make it look a bit more exciting.
<They can be very pretty.>
The filter is an HOB that does about 100gph, and the light is a CFL that screws into its socket; I believe I have about 2 wpg. I have a couple questions about stocking and tank size. How big exactly do these crabs get?
<Big, with carapaces reportedly up to 6' (~15cm) across.>
I was under the impression that they only reached about 7cm or so, but I read recently that they can reach 10-15cm.
<Yep, and the larger they get, the more their appetite, need for larger shells, and tendency to knock things about, increases. One thing I'm unsure of is how long it takes for these hermits to attain such a large size. I imagine it would take more than just a couple of years.>
Would it be wise to upgrade to a 10 gallon setup if I plan to add other animals to the tank?
<Yes, bigger is better when it comes to keeping water parameters stable and livestock healthy, so I'd recommend going as big as you can afford.>
If I upgrade, I will be using a hood made for 2 incandescent bulbs, and will be using 2 Coralife mini CFL 50/50 bulbs (http://www.petsmart.com/product/index.jsp?productId=2753932&lmdn=Product+Type). If I don't upgrade, I will use only one of these 50/50 bulbs. (I am doing this with my anemones, and possibly any other sessile inverts that I buy, in mind.)
<Okay, just be sure to keep the hermits well fed with a variety of sinking pellets, and/or meaty bits of marine origin like shrimp, clam, fish, squid, etc.. This will help deter the hermits from preying on some of those sessile inverts (particularly any small bivalves), resting fishes or snails.>
I am asking this because I have heard that hermits can be aggressive and opportunistic and may attack small sleeping fish,
<Yep, there's no telling what a hungry hermit will pick at or try to grab.>
..and I plan to add a small damsel
<Personally, I wouldn't add a Damsel to any system smaller than 20 gallons. They're active swimmers that can be pretty feisty on the best of days, much less when they're confined.>
..and goby,
<Gobies are great. Again, just be sure to keep those hermits well fed.>
..as well as some snails and a serpent star, without the crabs harming them.
<I'd hold off on the serpent star until you have a larger system.>
Thanks very much for your time,
<You're very welcome.>
<Take care, Lynn Z>

Hermit questions, rescued   -- 7/14/10
We went to the Gulf of Mexico beach in Mississippi, to look at the tar balls (from the Deep Water Horizon oil flow) washing up on the beach first hand (as we live close by). While we were there, we noticed hundreds (even
thousands) of hermit crabs on the beach (not moving and laying in oil). My daughter, who is 10 yrs old, wanted to try to "save" some of the crabs.
Against our better judgment, we did exactly that. We collected about 75 hermit crabs and then went to Pet smart to get supplies for them. The employees at Pet smart didn't know anything about care for this type of hermit. I have read through your site, but there is so much info, that I can't find what I'm looking for. We have the crabs at home, have bathed them in saline water (Hermit crab salt treated) and fresh (Hermit Safe treated) water. There is no oil residue left on them and they are moving and somewhat active. We have them broken down in many different aquariums, due to the number that we have. A few questions:
1) Should they be kept in an aquarium filled with water?
2) Should they be kept in an Aquari filled with sand?
<Mmm, depends on the species involved, but these read-like amphibious ones... need an environment in which they can be underwater as well as on dry land>
They move more when in water than if they are in a tank with only dishes of water.
3) Any idea of where I can bring some of them, as we cannot keep 75 crabs?
<You might try a local-enough public aquarium, fish stores, Craig's List>
4) Any other ideas that are beneficial or suggestions that you have?
<I'd get these to someone who can and will care for them ASAP... Bob Fenner>
Thanks for all of your help.

Red Hairy Legged Hermit in Refugium?   3/27/10
<Hello Heather>
I have a giant red hairy legged hermit, about the size of a closed fist of a young adult (not a full grown man) including the shell.
<Yikes! A real pincher!>
I am looking for someone to adopt him as I can no longer take care of two tanks. There is someone interested in my crab and wants to put it in a 75g refugium. With 20-25g reserved for the skimmer, my crab would have approximately a 50g space with LR. Right now he's in a 30g. I've read that some inhabitants are risky for a refugium. Would this be a bad new home for him?
<Very likely a good home... it may eat some of the inhabitants, but will not consume all>
Shelburne, VT
<Oh, the town of my U.S. publisher. Bob Fenner>

Our poor crab! Hermit homes    3/25/10
<Hi Shell>
We have 3 small hermit crabs in our marine tank, we recently put in around 15 new shells for our crabs to change into, 2 of them have happily changed shells and are enjoying the extra room, however the other crab is naked!
<Marine voyeurism! Not a pretty sight, eh?>
We spotted him the other night in a hole in the live rock, we watched him and he hitched a ride with one of the other crabs to move down the rock but then disappeared into the rock again. We have no idea why he has not chose another shell to go into, will he die?
<Unless there is something that can eat him, he should not. The other crabs might be a risk. Are none of the shells that you have put in suitable for him? I suspect he will find and take one of these on>
Any help would be greatly appreciated.
<I don't think there is much you can do here, apart from cover your eyes and hope he puts some clothes on! Perhaps you could separate the other crabs from him temporarily until that happens>
Many thanks,
<No problem>

Staghorn Hermit Crabs 3/19/10
<Hi Joe>
Do Staghorn hermits outgrow their shells, or do their shells grow with them?
<The Staghorn Hermit Crab lives in a branching shell that does not grow with them and is covered with hydroids and bryozoans. The crab itself is hardy, but the shell that it resides in requires specialized care due to the life
forms present on it. The problem with keeping this crab is that the shell can easily be overturned by other animals that may be present in the aquarium. Once this happens,
the crab cannot right itself due to the shape of the shell. Staghorn hermits are best kept in a system with other filter feeding invertebrates, or in a refugium where the hydroids and bryozoans on its shell can be fed properly with types of live or prepared plankton foods.>
<You're welcome. James (Salty Dog)>

Please help! (More hermit crabs!) 08/05/09
I brought home a crab from the beach who was not shy once he got used to me.
<Crabs are indeed bold and opportunistic; their heavy shells and strong pincers give them a certain amount of security from predators, so you'll often find them less nervous than shrimps and other such animals.>
About a week after getting John Conner, the crab, my family went out of town for 3 days. I made sure they had plenty of fresh water and lots of food.
<Why "fresh water"? Just to clarify here, do you mean freshwater, as in dechlorinated tap water, or a fresh container of seawater, which most land crabs from beach-type habitats will need to dip into. Seawater from a marine aquarium, if you have one, will be adequate, but being land animals, land crabs do need high humidity and air temperature too, at least 22 degrees C (72 degrees F). At minimum, a small land crab will need a tank 10-20 gallons in size with a pool 5 cm/2 inches in depth containing seawater; an under tank heater; and plenty of coir (coconut fibre) to create the "land" part above a simple bed of gravel used to secure the pool in place. Without a filter, the water should be changed every day or two. Use a sprayer to mist the land with dechlorinated tap water (not seawater) daily. A secure lid is essential; a plain Perspex or glass sheet is fine, but put the lid on slightly ajar so there's a flow of air in and out of the tank. I mention all these things because lots of people think they can keep crabs in very small plastic containers without any thought for their need for heat, humidity, or security.>
When I got back, I changed their nasty water and gave them more food even though they still ad some. The next day, he was acting really shy.
<May well be dying if you aren't doing the things listed above.>
He moved further into his shell when I picked him up and I didn't see him come out very much. I have two other shy crabs but that's just how they are. They are my first hermit crabs and I am very worried. Please Help!
<There's a very good site on Hermit Crabs, here:
Do note that the types that use freshwater for bathing are likely NOT the types you'll find on, say, a Florida beach. If you collected your crab on the beach, then it's a species that needs salty water for bathing. It's
actually a bad idea to collect wild animals without first checking ambient conditions in that location: salinity, temperature, humidity. The vast majority of "pets" dragged home from beaches die very quickly. Cheers,
Re: Please help! (More hermit crabs!) 08/05/09

Thank you! I forgot to ask if they need fresh and salt water or just salt water. Could he possibly be molting or not?? Thanks!
<They need fresh water or salt water depending on the species. Since you collected these crabs from a beach, then seawater is what they need: 35 grammes of marine salt mix (not cooking salt, not tonic salt) per litre of water. There would be no harm putting a shallow dish of freshwater in the vivarium also, to see if they drink from it, but for marine animals -- which they are -- the seawater pool will be essential. Without seawater, it will quickly die.>
Live, Love, Laugh,
<Cheers, Neale.>

Land crab or marine crab? Reading  4/29/09
Hi. I hope you can help me. I have read a lot of what you have posted, but I had a few questions.
We picked up a hermit crab from the beach on the gulf coast of Mississippi. We did not discover him until I went to clean the shells we found several days later. When I discovered him, I immediately put him
into a container filled with some sand I had sand and a bowl of de-chlorinated water.
<... won't work. These animals need full-strength seawater, filtration, heat>
I tried researching for several hours on the internet to find out what this was I had discovered and how to keep it alive.
From what I can tell, it appears to be a Clibanarius vittatus (Thinstripe hermit??) I am pretty sure cause he looks just like the picture. His shell is kind of large at about 1.5 inches in diameter.
Some websites suggested I feed him raw veggies or fruit. I have not been able to get him to eat anything. I also gave him two old seashells I had in my collection, but he has shown no interest in them. He did get
into the water and sit for some time, but other then that he just walks around.
Since I found him on the shore of the gulf ocean, I assumed he was a saltwater crab, but the aquarium store said it was a land crab??
<Many such false crabs are to an extent emersed in habit>
(without even looking at him. He was quite rude.) He wouldn't help me or offer any information that could direct me. So, today I went to my local PetSmart and purchased a beginner hermit crab kit with a cage, two bowls and two shells, and some hermit crab food. I hope he eats it, because it does not appear he has eaten in a week. How often do hermit crabs eat?
<A bit most every day>
Does he need fresh water and salt water?
Is it odd that he will not change shells or am I doing something wrong with the shells?
<Only change shells with need, growth...>
How can I tell if it is healthy? How can I tell the sex? Should I buy it a friend?
Thank you for your time!
Barbara Morgan
<Please read here: http://wetwebmedia.com/hermitsysfaqs.htm
and the linked files above. Bob Fenner>

Hermit Crab Restaurant Refugee. 4/14/2009
Hey guys,
<Hello Jenna>
I work in a seafood restaurant and we get deliveries of oysters from a local supplier a few times a week. The oysters come in bags, and sometimes there are a few stray creatures in the bags with them. The guys that shuck and steam the oysters always set aside the crabs they find and give them to me. I have a brackish water tank with some minnows in it, and I put the crabs in there.
<That does run the risk of introducing parasites, but as long as you are comfortable and aware, that is fine.>
Tonight they found a hermit crab in the bag with the oysters, and they gave him to me. I know that if he was in the bag with the oysters then he had to have been caught in the water.
His shell is covered in barnacles, which also would seem to imply that he lived in the water. I was wondering if this crab lives solely in the water, or if I need to put him in a tank with some kind of dry land in it.
I know that land hermit crabs will drown, but I don't know what this hermit crab needs.
<Difficult to tell without a picture, and even then, it isn't exactly easy.>
So, can I put him in my tank (just water) or do I need to make a tank for him that has both water and dry land?
<Based upon you description, it is likely not a land hermit. I would add it to the tank.>
Thanks for your help
<My pleasure>

Hermit crab - freshwater or saltwater? 12/2/08 Hi there folks! I recently went to Baja, on the east side (Sea of Cortez). We collected shells on the beach (I know, not always a good idea), and though we checked them all pretty thoroughly, we ended up with a tagalong. He must have recently changed shells, because when he hides you can't see him even if you peer inside the shell! Anyway, he survived for 5 days out of water in transit and now I am looking for a home for him since Baja is 12 hours driving away from here. I am fairly certain he is a Clibanarius vittatus. I got some saltwater from the fish tanks at the pet store and fed him a dead snail (don't worry - the snail was already dead and stinky when we picked up the shell), so he's happy for the moment. Now to try to find him a home. I have lots of people asking me if this species can survive in temperate freshwater. From what I've read, it seems they need at least brackish water, and preferably a proper saltwater tank with room to crawl out of the water. Am I correct or can they also survive in freshwater? If all else fails, a saltwater aquarium store in the next town from here said they would take him. Thanks! -Ramey <Hello Ramey. Many Clibanarius species are euryhaline, meaning that they can adapt to varying salinity, at least for a certain length of time. Even the common blue-legged hermit (Clibanarius tricolor) sold as "clean up crew" for reef tanks is a euryhaline species that does well in brackish water down to about half-strength normal seawater salinity (roughly SG 1.010 at 25 C). At least one species sometimes get sold as a freshwater hermit, Clibanarius africanus. But in the long term, freshwater doesn't suit any of them. It may take weeks or months for things to go wrong, but they do. In the case of Clibanarius vittatus, the optimal salinity is a middle brackish salinity if distribution in the wild is anything to go by; while they are found in normal marine (i.e., full salinity) habitats, they are commonest in estuarine habitats where salinity is relatively low. Half-strength seawater is just about perfect. While they will adapt to fully marine conditions permanently, I strongly doubt they will survive indefinitely in a freshwater aquarium. Cheers, Neale.> Re: Hermit crab - freshwater or saltwater? (Clibanarius vittatus) Thank you for the advice! I will make sure he goes to a marine or brackish aquarium, then! <Happy to help. Good luck, Neale.>

Beach found hermits 09/27/2008 hi crew, <<Hello, Andrew today>> I have a small one gallon tank to hold about 8 very small hermit crabs that I found on the beach. I filled the bottom with beach sand and used ocean water. I have only had it for about 3 days and the water is starting to smell of dead fish and grow black mold through the top of the tank. is this normal?? are my little crabby friends in danger? help! <<Sounds like a lack of filtration / flow to me. Would replace water with synthetic seawater. Thanks for the question, hope this helps. A Nixon>> <... need a bit more input than this. B>

Does Clibanarius vittatus need land? 08/08/2008 Hi guys, <<And Gals I hope. Andrew here today>> Judging by the hours of research online, I'm pretty sure our hermit is a Clibanarius vittatus (striped hermit crab). In a moment of stupidity we allowed our son to bring it back to Texas from the bay in the Florida panhandle. We actually wound up with two, thinking the other was a shell (lesson learned!). <<he he he>> On the advice of a local saltwater fish store, we set up a 10 gallon tank with dechlorinated water and Instant Ocean, crushed coral, a hydrometer, an in-tank filter, empty shells and a large rock. We have been feeding them shrimp pellets. One lasted 4 days then died. He was never active and seemed more stressed - frequently changing shells, then losing a couple legs. The other has been quite active since we put him in and seems to be doing okay. At least once a day he climbs to the top of the rock so he's partly out of the water. He also tried to climb the side of the tank. Question 1: Does he need a different aquarium set up with more land? <<Some land for this hermit is fine, it can spend a few days out of water>> Question 2: Does he need any kind of heater? Our room temp is around 74F. (The pet store guy said no, but I thought you'd know better.) <<That temperature is fine. If it starts to drop hen maybe switch to using a heater>> Question 3: Are shrimp pellets appropriate food? <<Sounds fine. provide a little algae matter / meaty bits in the diet>> Question 4: Will he dig under the coral to molt? How much substrate should be on the bottom of the tank? <<Not much substrate is really needed. Clibanarius vittatus will look for a sheltered spot, which it feels comfortable in to molt>> Thanks in advance for your help and for your great site. We'll never again remove a critter from his natural habitat, but now that we have we want to do the best we can for him. <<A lesson learned perhaps. Please do be aware that these DO get large>> Laurel <<Thanks for the questions, hope this helps. A Nixon>>
Re: Does Clibanarius vittatus need land? 08/12/2008
Hi Andrew (and all the other guys and gals!), <<Hi>> Thanks for your zippy and helpful reply! I have a few quick follow-up questions: <<Ok>> The only semi-dry land he has right now is the tip of a rock sticking out of the water. Is that enough? I understand he can spend time out of the water, but does he need to? Do I need to provide more than that? <<As long as it has space to walk / move around, shouldn't be so bad.. Maybe add some base marine rock in an area to provide land?? How big can he get? Is the 10 gallon tank enough? (He has 4 empty, larger shells in there now). <<These can grow to around 10 - 15cm. If you plan to keep, would maybe suggest a nice 20 gal tank for it as it grows>> Do these guys like to have company or do they do better alone? <<Same as a lot of hermits in the aquarium, they usually just go about their own business>> Again, thanks. You guys are a great resource!! Laurel <<Thanks for the follow-up, hope this helps. A Nixon>>

Marine Hermit Crab Questions... sys.   8/03/08 Hello! <Hi there> Over the Past couple weeks I have read over your many submissions pertaining to marine hermit crabs, which have been very interesting and have answered several of my own questions involving marine hermit crabs (specifically regarding identifying specific species of marine hermits, feeding them, and their substrate needs). I have also bought a book, ?Marine Reef Aquarium Handbook? by Robert Gold, which was also a good read. <Thank you for this reference, endorsement> I have been keeping land hermit crabs for several years now, six species in total; four in the US (c. clypeatus, c. compressus, c. rugosus, and c. perlatus) and two while I lived in Australia (c. variabilis, c. purpureus). So now I am interested in keeping a couple species of marine hermit crabs (I think Clibanarius tricolor, Clibanarius vittatus, and Paguristes cadenati), in a small sized tank (most likely a 10 gallon). I know that smaller marine tanks are more difficult to keep, but space is at a premium in my small apartment.  The only things I wish to put in my tank are the marine hermits, live rock, ?dead? coral, and other various aquarium ornaments. Unfortunately, most of the information online and in books involves keeping marine tanks in general, not simply meeting the needs of hermits. So I have several questions: 1) What ranges do I need to have my specific gravity in for the crabs? <Mmm, for the stated species, close to NSW strength... 1.025-6... depending on what device you use for measure (best a refractometer). A good idea to pre-mix and store new water, change out small/er amounts more frequently (a gallon or so a week)... to prevent drift> What temperature range? <Lower to upper 70s F.> I think that I will be using the ?Berlin? system of filtering, with brilliant lighting, live rock, and a protein skimmer. What ranges do I need to keep the levels of phosphate, nitrates, nitrites, pH, etc, to keep the crabs healthy? <Low on the first two... under 0.1 and 20 ppm respectively, no nitrite... pH in the 8.2-8.4 range is ideal.> 2) How often do I need to change the water? A 10% change every week? <Bingo> 3) What is the maximum number of marine hermits (if the crabs are roughly the size of a black-eyed pea) that I could safely fit inside a 10 gallon aquarium provided that I have the proper number of shells and hiding places? <Maybe eight or ten... if someone is hungry, someone else is shedding, otherwise impugned... they may become feeder/fed> I realize, of course, that they will molt and grow, especially the c. vittatus, but I will be sure to take that into account. 4) ?Dead? (for a better description) coral is all right to use in the tank, correct? <Yes> I'm not interested in keeping live coral (and I understand that Paguristes cadenati in particular might nibble on it if I did), but my land hermits enjoy climbing on the coral, so I assume marine hermits would too. <Correct> Thank You! Caroline Beyer <Welcome! Bob Fenner>

Question (please answer) A Long Way From Home - 7/23/08 Hermit crabs collected... Hi. <Hello> I have three large hermit crabs (2 1/2"- 3") and two smaller hermit crabs (1/2") that my family brought home from Galveston. <This story never ends well...> We were staying by the ocean, and found them in tide pools. I have no idea the species, what they should eat, or what to do. <Then pray tell, why did you think you could keep them? These are living things, not curio souvenirs!> We have set up a small tank, with land and water (we brought water from the ocean). <Only 'need' water, most likely> I regret bringing them now that one has died, but it is too late and too far to return to that beach. We live closer to the "middle" of the country, and can't return them to any beach. Not that I would put them in a colder sea, anyway. <So you're saying you would feel qualms about putting these crabs in a foreign environment, but had no reservations about trying to keep them yourself, despite no idea how? I don't intend to me mean, but the lack of foresight is stunning.> The water where they naturally lived was warm. Should I try to maintain that? <If I put you in a bubble, would you want me to emulate our environment, or is one with cyanide instead of nitrogen okay?> How can I recreate their sea home? I cannot seem to find anything they eat. It stays there for days and eventually I just have to re-clean the tank. What would they eat in Galveston, anyway? What species is it (most likely)? We have natural shells, some seaweed, and one odd plant on a shell (not identified, but we are trying). We originally thought they would do well with our other hermit crabs, but our other hermit crabs are land crabs, and these are in the water almost all the time. One of the larger marine crabs are almost always on land. Should I be worried? Also, if the smaller crabs are always climbing on the larger crabs, should I make a smaller tank for just the small ones? The larger ones sometimes claw at the small ones. <Gina, you're going to need to set up a small heated, filtered saltwater aquarium for these crabs. Read how through the search feature on www.wetwebmedia.com. These crabs will need to be fed fine bits of food of meaty origin, fish, squid, shrimp, etc. In the future, please try to let mother nature take care of her living things, unless you are already equipped to give back at least some modicum of what you take from them by removing them from their original home> Thanks, please answer as soon as you can, Gina & family <Benjamin>

Blue legged hermits. alone   7/14/08 Greetings! <Hello! Benjamin here.> I have Googled forever and I can't find a situation like mine.... Through the years I have had experience adopting (or inheriting) a variety of unwanted, often aged, pets via friends of friends of friends. This has slowed greatly recently due to a family circumstance, but now I have to find out how to care for three blue legged hermits. I am knowledgeable about land hermit crabs, but not marine so I searched the net. I put the blue legs into a one gallon glass aquarium with instant ocean, calcium sand and, on one end, some gravel. According to the hydrometer everything is good (a miracle because I have no experience with saltwater tanks). I have a Whisper power filter running in the tank (the kind that makes a "waterfall") and it is going at a low setting. I have fed the blue legs bottom feeder food, crab bites, algae wafers and some vegetable matter. I have kept them a couple months in this manner and they are active and have good appetites. Things like the hydrometer, calcium sand, etc., I bought just to take care of these guys, but now I wonder if they can thrive long term without other creatures to clean up after and no live rock, etc. I enjoy caring for them and learning and I want to keep them. I am afraid even if a LFS would take them from me they might simply dispose of them. I know they are "just crabs" but can you tell me if I am on the right track? I have heard about "shrimp only" fresh water tanks, but a "crab only" saltwater tank? <Sounds like you've given them everything they need to survive. Do be advised it is very hard to truly emulate the environment of any captive creature, but if you wanted to give a more complete environment I'm sure a large reef aquarium would be appreciated by these crustaceans- and probably you too!- though not necessary. If all you want to do is house these crabs to the end of their days, your 'crab only' tank should be just fine.> You are an awesome resource! <Thanks, we appreciate it.> Thank you! <Welcome, Benjamin>
Re: Blue legged hermits alone? - 7/14/08   7/23/08
Thank you for the fast and helpful answer. My mistake, I have a two and a half gallon aquarium, not a one gallon. I have a hex tank that is at least 5 gallons that I could put them into, but I don't know if they would like water that deep. <Depth really doesn't help much...but pile some live rock in there, and you've got some very happy crabs- and have begun down the path to a reef aquarium!> The three Blue Legs are active and one molted a couple weeks ago. <Sounds like they're healthy. Make sure you have a few extra shells for them to move in to as they grow, and that they get plenty of proteinaceous foods> Thanks again! <No problem! Benjamin>

Hermits From The Gulf - 06/07/2008 Hi, <Hi, Nick. Sabrina with you today.> I have been reading your site now for an hour or so but still have a few questions about my specific situation. Any help would be greatly appreciated. <Okidoki.> I caught 5 quarter-sized hermit crabs off the gulf coast of FL on vacation 4 days ago; they were collected in knee-deep ocean water. Here is a very similar picture: http://njscuba.net/zzz_uw/srb_hermit_crab_1.jpg . <Similar is often not the same, so I would be wary of trying to make an ID off of a photo of a similar animal.> I have been keeping them in a plastic container with lava rocks and a few extra shells, but now need to set up something more permanent (no chance of returning, we're now in TN). <Just a quick note here to others that may read and benefit from this.... I do strongly recommend against collecting critters unless/until you already have a system set up to keep the animals thriving.> I changed their water daily while we were there (used nearby brackish water)- whenever I did this they went crazy moving around and filtering, <"And filtering" you say - what do you mean by this? Do these animals have filter feeding appendages? I'm not sure I follow....> and got along great. However, fresh brackish water <Were these buggers in brackish water or salt/ocean water?> is not quite in abundance in TN. <Heh! No, I'd guess not!> Here are my questions: <Okay!> 1) I have tried to feed them very small pieces of turkey, <Skip the turkey, oh please.> fish flakes, and small pieces of fruit, but they don't seem to go for any of it. What common food would be a greater success, <Human consumption fish, shrimp, crab, shellfish.... Freeze first or buy frozen, to prevent introduction of pathogens. Seaweeds - sushi Nori from an Asian market would be great. Any of these foods, if eaten, will be fine. I am concerned, though, about your comment of "filtering". If these animals are filter feeders, you are up for real troubles.> or is it mandatory to buy commercial food? <Nah. Unless these are really filter feeding animals. If so, you might consider DT's Phytoplankton, or some of the products from Reef Nutrition.> 2) I have a 10 gal. tank, instant ocean, chlorine remover, thermometer, and a filtering system. I realize I will need a hydrometer. <Yes, and urgently. Or a refractometer.> Is there anything else I *absolutely* have to have? (trying to keep cost a minimum here) <A manner of providing calcium, iodine....> 3) How deep should I fill a ten gallon tank with water for the 5 crabs? <If they don't appear to spend much time out of the water, then "completely" is your answer. The more water the better. A ten gallon tank is extremely difficult to keep stable.> 4) What filler should be used (sand, gravel, etc.) and how much? <Calcium carbonate substrate of some sort.... Aragonite sand would be my choice, but crushed coral would do if the former cannot be found.> Should any land be provided? (Crabs have been submersed nearly entire time I've had them) <If they don't appear to spend time out of the water, then a land area is probably unnecessary.> 5) Best way to introduce crabs to new water?, <Slowly, with a drip acclimation perhaps, over a few hours at least.> and 6) Anything essential I'm leaving out here? <Just more research.... This is an entirely "doable" project, but do please keep reading, researching.... I expect you'll even really find this enjoyable! My best regards to your crabby pals, -Sabrina C. Fullhart>

Hermits From The Gulf - II - 06/07/2008  6/9/08 Thank you very much for your help! It's great to have a post where questions are actually answered and answered well at that. <Thank you very much for your kind words.> As for your questions, I collected the crabs in the ocean and refilled the water from a small mudflat nearby connected to the ocean (evidently they're not too choosy about brackish/seawater). <Did you find any of the same crabs living in the water at the mudflat? Happen to know the salinity of it? Many invertebrates actually *are* quite fussy about salinity and other factors of the water; do please be cautious here.> Whenever I introduced new water, the crabs would immediately start roving all over the place, <Keep in mind that increased activity level can indicate very different things - it could be that they are loving the new, clean water with nice little bits of stuff in it, but it could also be that they're really stressing from the sudden change in water parameters.... trying to find a way out, basically.> moving extremely small pincer-like appendages to their mouths back and forth repeatedly. It seemed to me like they were "filtering" little particles out of the water, but I may be wrong. <Maybe.... tough to say.> I have now tried feeding them small shrimp pellets but haven't seen them make a move on those either (unless they're just sneakily eating little pieces while I'm not watching,) They have in fact been unusually inactive these last couple days without water change. <Not a good sign. If they're in a small space with no new water, they could be on their way to being doomed - please get some new water mixed up and ready as soon as possible.> They most resemble the Clibanarius vittatus on your site, but my crabs are completely white and are smooth-shelled. <Maybe the same, similar, or completely different species, then. Any chance at a photo of them?> Upon closer inspection I noticed two small "things" within the mouth on either side are continuously moving up and down rapidly even when the crabs are out of water (not the small pincer-like appendages I referred to earlier). <These sound like the antennules (err, at least, I think that's what they're called.... I fear I'm a touch rusty on crabby anatomy) that they use to smell and taste.> Hope my new essay provides some insight :) <Mostly, your key task is going to be to provide them as close to an accurate environment as possible. If you can get an image of them, or if you do seriously feel that they are filter feeders, you might try taking frozen foods like Ocean Nutrition's "Formula One" and "Formula Two" foods and squish them up in the water as best as possible to see if maybe that will help them to eat. I'm most concerned about their water quality and the fact that they've been inactive - please do get them into as suitable a space as you can. Please keep reading - a beginning saltwater book such as "The New Marine Aquarium" by Michael Paletta might be a worthwhile read for you. There's *tons* of information on this site, as well, and you might also take a peek at our forums - http://bb.wetwebmedia.com . There are many helpful folks there who can help steer you right as well. Keep at it - your crabs will thank you for your research, and I do seriously think you'll get a great deal of fun out of this! Best of luck, -Sabrina C. Fullhart>

Hermits From The Gulf - III - 06/09/2008 Thanks again for all the help! I'm drip acclimating the crabs now and they seem to be perking up. <Excellent, glad to hear it. Wishing you well, -Sabrina>

Hermit Crab Shells 03/06/2008 Hi! Brian here with another question! I picked up a few large hermit crabs from the LFS about a month ago. They seem to be happy munching away at the algae and scraping the gravel. They are pretty fun to watch (I know? usually crabs are the boring ones, right? Hehe). I was absolutely surprised at how quick they moved and how well they climb some vertical rocks that I have! Here's my question, I hope you can help. I'm looking for shells for these guys. They are quite big, I would say at least 3 inches long in shell. I can't find any for them to grow into! The fish store I bought them from told me they put the word out to look for some, and they did manage to get me 2, but I've got 4 crabs. All the one's I've seen locally are for the smaller hermits and I'm wary of just buying shells online because I don't know if they are lacquered and all that. Know any place I might be able to get some? <<Ebay.com and the shop is called " The Hermit Crab Shack "..They sell a wide selection of shells that are suitable for use in the aquarium.. http://stores.ebay.com/The-Hermit-Crab-Shack >> Did I say one question? Sorry, here's another one. <<He he he he....there's always just one more...>> I also just recently purchased a yellow tang. He's been picking at my live rocks, but is there anything else I can supplement his food with? Is it even necessary? The LFS said they fed him Emerald Entrée? and Ocean Nutrition Seaweed Select, but their holding tanks don't have live rocks. Should I grab some and offer them or is he going to be happy just picking at the rocks? <<For sure. Offer a variety of algae based foods such as the above and Nori sheets>> I've got a 125gal FOWLR with about 150lbs of live rock. There is algae growing on them, green, green hair, some type of reddish looking algae. Ammonia, Nitrite, Nitrate are 0. In there with him are 1 4stripe damsel, 1 coral Hawkfish, 1 red barred goatfish, 1 Sargassum trigger. <<Feeding as above, and I am sure it will get its correct diet and fill each day>> Thanks a lot for the website and amazing book (Conscientious Marine Aquarist)! <<Thanks for the questions, hope this helps. A Nixon>>

Hermit crab of Thailand traveled to Holland... ID, care  - 08/27/07 L.S., 17 august our son took with him a nice, empty (so we thought) shell. We were on holiday in Thailand. He found the shell at the beach at the island Ko Pha Ngan in the Gulf of Thailand. After more than 24 hours of traveling we exposed the shell at home on a table and had a look at it once in a while (dreaming about Ko Pha Ngan). Saturday evening (25 august) we looked at it again and saw it walking! The shell obviously was not so empty as we thought. We think it is a marine hermit crab. The shell is about 7 cm long. The crab has dark brown paws with little hair and blue stripes. I asked my son and he told me he found the shell at the beach, near the coral, but within the range of tide. I would have loved to bring back the poor animal. Unfortunately, Thailand is so far away. So I called the Zoo of Rotterdam and asked them if they could take care of our new pet. They will!!! We brought it yesterday to the zoo. They will investigate which kind of hermit crab it is but I am not sure if they succeed (they have so many animals to take care of.). So I looked on Internet to see if I can learn more about hermit crabs. At that moment I found your marvelous site. I hope you or the forum could help me in identifying the creature. Attached you'll find a picture of the crab. Maybe one glance at it is enough to identify the animal? If so, I can inform the Zoo so they can take even better care of the crab. We hope you will have a look at the picture. I tried to post this message on the forum but unfortunately this was not possible (the sign-in process was the problem). Thanks a lot for answering, Best regards Annemarij <Hallo Annemarij! The crab looks like a Clibanarius sp. hermit crab. These are quite common in the aquarium trade. They are very hardy animals and easy to keep. There are many species, some found in freshwater, brackish, and marine environments. Many species are intertidal animals, adapted to quite extreme changes in temperature and salinity. This is probably why they do so well in aquaria! The feed mostly on algae and organic detritus. Marine aquarists usually keep Clibanarius tricolor, a marine/brackish water species; freshwater aquarists may sometimes be offered Clibanarius africanus. Assuming you found your specimen on a saltwater beach, then you should keep the hermit crab in a tropical marine aquarium. Generally these hermit crabs are unproblematic. The only issue when keeping hermit crabs is they need access to empty shells as they grow. I hope this helps, Neale>

Re: hermit crab of Thailand traveled to Holland 8/28/07 Dear Neale, Thanks a lot for answering my mail! It certainly help me. I'll inform the Zoo Blijdorp of Rotterdam and hope that 'our' crab will have a happy and long life. Again, many thanks. Best regards, Annemarij <You're most welcome, and I'm glad the little crab is going to have a pleasant life at such a nice zoo. Cheers, Neale>

Marine hermit crabs? ID, care  - 08/27/07 This past weekend I was in Cape Cod, MA. Some friends and I were in the ocean (just ankle deep), and we saw a bunch of tiny hermit crabs in the water. They are only the size of my thumb nail, maybe slightly larger. Well of course we made the dumb decision to bring some home, and now I have 4 of them in a water bottle with salt water and sand and rocks in it. So far they are fine. I went to a pet store today and bought a bunch of stuff for them. But once I got home and did more research I am realizing to my horror that I don't think these are land hermit crabs like I was thinking. Can I keep them in captivity or will they die?? I bought a little plastic container and sand and a sponge for them, but I think they need to be fully submersed in salt water don't they?? Should I get a whole salt water aquarium system for them?? I'm not finding much info on how to care for Marine hermit crabs, and I'm afraid these cute little guys will be dead any day now!!!!!! Please help!!! Thanks. Natasha (If you need a picture of them to identify I can send one later.) <Hello Natasha. Identifying a hermit crab to species level is very difficult without a photo. But in the cooler parts of the North Atlantic then species of the genus Pagurus are most common, both along the North American and European coasts. So I'm assuming you have one of those. They are indeed fully aquatic hermit crabs, though they are well able to tolerate exposure to air for some time, and will scuttle about in very shallow water even with half their bodies exposed. But for long term care you will need to set them up a "coldwater marine" aquarium. This is not difficult. Firstly, you'll need a tank around the 10 gallon mark. Then you'll need a filter. I'd recommend a simple air-powered box filter filled with ceramic media and a bit of filter wool. There's no need for carbon or anything else. The aquarium needs to be filled with artificial seawater -- that is, water with about 35 grammes of *marine aquarium salt mix* added per litre of water. Using a hydrometer you need to aim for a specific gravity of about 1.027 at 18 degrees C, the maximum safe temperature for these crabs. Try and keep them cooler if you can. I have a little program called 'Brack Calc' on my web page ( http://homepage.mac.com/nmonks/ ) that lets you relate the required salinity (35 g/l) with whatever temperature you have and the specific gravity you can directly measure. Beyond this, keeping hermit crabs is easy as they are quite hardy and adaptable. They are omnivores, mostly feeding on algae, organic detritus, and carrion. In the aquarium almost anything will be accepted, from algae pellets to raw seafood. Don't overfeed them though. Apart from the fact these animals don't need extra light and don't like warmth, in terms of basic care they are otherwise similar to tropical marine hermit crabs. Hope this helps, Neale>

How did I find this site? Was it luck? Need advice on Hermit Crabs. I'm not stupid, but I sure am ignorant. We All Started Somewhere; A worried newcomer and his hermits/tank  - 05/08/07 <Ferrari I apologize in advance I took a little longer to get back to you, but I placed this query aside because I wanted to ensure it got special attention and that you got pointed in a positive and correct direction..., good luck to you and your animals.> I have been reading for about 2 hours... <Addicted yet?> Now, I realize my ignorance, <That's okay…the first step is admitting it, and on the plus you are here to correct your mistakes I presume. That's all we can ask.> but I will listen to your advice and return the 4 hermit crabs to the bay. <Okay, hold off my friend.  Once you collect animals form their natural habitat and place them into artificial quarters, it would not be ethical to return them, though I understand your heart/logic is in the right place.  You see returning them would put the wild-population at risk, you could introduce non-native behaviors and/or pathogens, which could severely destabilize the natural ecosystem. Unfortunately if you can't provide the right environment to these critters or know someone who can…..the only option is humane euthanization.> Here is my total life experience with Aquariums. <Okay…we all started somewhere.> Last week-- Knew nothing about Aquariums. 3 days ago I found two 20 gallon tanks at a thrift shop. 2 days ago I retrieved 4 Hermit crabs and 10 gallons of water from bay and set up one tank. <Okay the first mistake is the impulse collection. It is important to research the needs and have the set-up in place before collecting or purchasing animals (also check your local laws). The next mistake, in my experience/opinion…is the use of sea water vs. synthetic. See here; http://www.wetwebmedia.com/seawater.htm. Also you can't set-up an aquarium and introduce livestock in the same day, you must establish the biological filtration in the aquarium and let it go through a nitrogen cycle. See here; http://www.wetwebmedia.com/estbiofiltmar.htm .> Yesterday I added some nice looking shells for them to try on and fed the hermit crabs Tetra Crab Cake food pellets. <What would be most helpful in outlining a diet for these hermits is if you could identify where they came from or even better what species they are. Having said that I would try adding some variety to their diet. Look into frozen and freeze-dried aquarium foods, krill, squid, Mysis, mussels, notice that all of these items are of a marine origin not terrestrial or freshwater based (I'll make an exception for our friends over at P.E. Mysis which are freshwater based…but that's a special circumstance).> Last night I took a big step and bought a 55 Gallon tank kit from Wal-Mart, along with an extra AquaTech 30-60 Filter just to be sure.   <I see you have been bitten by the bug! Also look into more appropriate marine filtration on WWM. In particular I would recommend you look into live rock and I URGE you to seek out and purchase a quality protein skimmer. A nice Aqua-C hang on model would be appropriate for this set-up.> Taped a really nice looking reef background to the tank.  Washed then added 50 lbs of Wal-Mart beige colored river rock. <You may want to look into live rock or at least (marine-based_ porous/calcareous lime rock.> Next, treated 50 gallons of water with (Jungle) start-right water conditioner <This is good though there are some other brands of conditioners which I prefer. Tap is okay in certain areas though not ideal…..look into other sources of freshwater, including RODI water. Many local fish stores sell it a reasonable price of you can not purchase a unit yourself.> (5 gallons at a time) while mixing in a bag of Instant ocean to the 50 gallons of (tap) water.  Specific Gravity now of 1.021 <Will need to be higher for inverts (your hermits); http://www.wetwebmedia.com/marine/inverts/arthropoda/crabs/hermitcrabs.htm .> I bought rocks and ledges.    <Do you by chance; know what they are made of? I'm trying to see if they will be invert safe, many rocks contain lots of heavy metals which can prove fatal to your hermits.> Nice new home for four hermit crabs.   <It does sounds like you are trying, do not be so harsh on yourself. Though I would slow down slightly and read a little more before you get your feet wet…pun intended.> The real issue--->The water is not crystal clear, <This is expected with such freshly mixed sea-water and a new aquarium. How did you clean the rocks/sand used prior to putting them in the tank. As you will read in the cycling link I placed above…you will see that it might be some time before this aquarium is suitable for livestock.> so I bought new florescent bulbs 18,000 Kelvin ($20.00 for each bulb). Still I can not see the background reef.  The two filters have been running for 14 hours now.  Not cloudy water, just appears to be normal salt water. <Mmm…likely still debris settling, are you testing the water chemistry yet? http://www.wetwebmedia.com/watrqualmar.htm ; if not I would begin doing so, this will be a very important aspect in your new hobby.> I realize now that my issues are many, but really I would like to solve the issue of lighting the background before I tackle the other more pressing issues. <They are vaguely related. I also encourage you to keep reading not only on WWM but text books as well. Pick up a copy of Mike Paletta's 'New Marine Aquarium" and then move on to something like Bob's CMA.> So, I guess I should have just asked about the lighting issue, but I wanted to give you something to talk about when you WetWebMedia guys get together this morning. <I've actually only met 4 crew-members total, Bob included and we do not poke fun at the mishap at livestocking….sometimes we do laugh at the situations folks get in….but that's not meant maliciously it's mostly to keep from crying.> I do not want to replace the standard hoods and the Fluorescents with a Glass top and HO fluorescents unless I really have to.   <If you only plan on keeping the hermits, what you have (NO fluorescents) is fine.> I have an almost totally empty tank. what a starting place, huh? <Do not feel alone, this is everyone's starting place….and others have made far worse mistakes than you.> I am thinking of pulling out the Beige colored aquarium gravel and finding something reflective (perhaps White Crushed Coral), <The latter would be better, though I would even look into something finer. Read this too; http://www.wetwebmedia.com/marsubstr.htm .> and even stronger lighting.  Or is there a simpler solution? <The lighting is not an issue at the moment, see all of the above.> Seems like the lighting issue can run into the hundreds of dollars for a small 55 gallon tank, <Yes if your aim is to keep photosynthetic organisms…which you aren't at the moment. What you need to focus on is filtration equipment and the nitrogen cycle of your new tank(s) I must be doing something wrong. <We all did in the beginning do not stress, chin up my friend.> Thank you in advance, <Of course, feel free to email me back should you seek clarification.> Ferrari <Adam.>

Hermit crabs trapped in a moray eel cave - 04/26/07 Hello, Thank you for your web site. <I'm glad you like the site> I recently installed a PVC pipe cave under the substrate for my snowflake eel, and 2 of my hermit crabs have fallen in and they can't get out! <Happens.> I do not want to stick my hand in there and fish them out <me neither>, and I am worried that they will either starve, or be eaten. Any thoughts on how to keep them out? <First get them out if they cannot get out by themselves. They can climb on some materials, but fail with others. In such cases I put something tank safe in the moray eel cave, e.g. a long piece of air hose, a long cable wrap, whatever seems appropriate to you and is chemically inert in marine water. The hermits can use them as a kind of ladder and climb out. It will take them a while. Most seem to learn their lesson and stay out. I left the ladder items in some of my caves and cut them to the right length to make them barely visible.> Thank you, Gordon. <Cheers, Marco.>

Shell-less Hermit Crab - 04/22/07 Hi, <Hi Amanda, Mich here.> We have a 60 gallon tank with a variety of fish and 2 hermit crabs. The tank is doing great. My husband was doing our 10% water change and after he was done he saw something strange. He noticed what looked like a crab without a shell, so he checked on the 2 shells and both were occupied by their crabs. We decided that the 2 crabs we had, had mated so we ran to the pet store and bought some shells, however this crab is quite large to be a baby, and we have never seen it before today. <It is always a good idea to have a selection of extra shells, slightly larger than the ones the crabs currently live in available for the crabs to relocate to as they grow.  Most likely this crab hitchhiked it's way into your system.> I was wondering if you could shed some light on how this crab could have survived with out a shell and why we haven't seen it before today. <The crab could survive if there are no predators, but the other crabs in your system are a threat.  Hopefully the crab will find a new home from one of the shells you provided.> Thanks Amanda

Question Re: Pagurus samuelis sys. mostly  3/23/07 Hello, I find myself in possession of what I identified to be a Pagurus samuelis hermit crab. <An intertidal animal from N. America's west coast: http://www.rosario.wwc.edu/inverts/Arthropoda/Crustacea/Malacostraca/Eumalacostraca/Eucarida/ Decapoda/Anomura/Family_Paguridae/Pagurus_samuelis.html> Unable to return this little fellow back to the ocean, I want to replicate a habitat as best possible. <Okay> When I was given the hermit, it was in a small container with some beach sand and water, where the water was cloudy and the hermit was very sluggish. I immediately made some fresh instant ocean <Proper nouns, companies, their products, are capitalized> in another small container, and added a few shrimp pellets. Within an hour the hermit was lively again and was scrambling around the container & eating the pellets. <Good> Wanting to create a more permanent/stable environment, I would like to know how to create a habitat to keep my hermit happy. Is an all pellet diet sufficient? <Can be> If not, what else is recommended? <Please see below> While the hermit seems to enjoy clear water, how often should the water be changed? Although he always crawls to the bottom when I see him, is this type of hermit able to live 100% underwater? <No, not well or long> I've heard of live rocks and the sort, are these necessary? <A good idea for a few reasons> Can I just treat the hermit like any ocean hermit, or must I make his setup different since the hermit is tidal instead? <Needs to "get out" And how would/could I replicate this in a cost-effective way? <All posted: Please read here: http://www.wetwebmedia.com/marine/inverts/arthropoda/crabs/hermitcrabs.htm and the linked files above> If things work out, and I fly back out to CA sometime, what is a recommended means of transport? <Likely a small bag with a few drops of ambient/system water, sealed and tied (to prevent crushing)> (wouldn't want to check or expose to x-rays :-D) Also, how long can I expect this species to live? <Days to a few years> thanks so much & kudos to such an informative site! - J Lee <Please use it. Bob Fenner>

Clibanarius tricolor biotype  1/14/07 Hello Robert, <Neale> I can probably rustle up a few pictures. There are also some useful   sources on Wikipedia, which we used in my book (which I finally have   a preview copy of, by the way). So there's other options, too. <Have the ones you sent along, thanks. Will post with credit to you> Since you're a marine guy, perhaps you'll know whether the blue-leg hermit sold in the UK (Clibanarius tricolor) is the same as the one in the US. I've mentioned it in the article because it does well down to SG 1.010. I assume it's a rocky shore or estuarine species that gets collected as a cheap reef critter. But I don't know anything specific about its ecology. Can you enlighten? <I do think this is the same animal/species... and yes to its euryhaline tolerance> Cheers, Neale <BobF, out in HI... trying to catch up!>

Orphaned crabs   10/4/06 Dear WWM crew, <Tanja> Acquaintances of mine have recently bought their first saltwater aquarium. As it turns out, the crabs they bought like to breakfast on the fish. <Very common> I was handed the three crabs in a small water tank, and now I have no idea what species they are and what they need. I have spent hours searching the internet and your site for similar pictures: They are dark green, with thin light yellow stripes running down their legs vertically. The tops of their claws (is that what you call them?) are yellow also and both claws are the same size. They are about one inch long (including their hermit shell). <Oh, at least their anomurans... Hermits in this case> I called a local pet store and was told that they need a complete saltwater aquarium set of at least 20 gallons with filters and every other equipment fish would need as well. Is that true, or is there a way of keeping these kinds of hermit crabs on their own on a less pricy level? <Is so> Thank you so very much in advance for your help! Tanja D. <Please read here: http://www.wetwebmedia.com/marine/inverts/arthropoda/crabs/hermitcrabs.htm and the linked files above. RMF>

Alkalinity and hermit crabs... I'll say! Not even trying to read   8/23/06 Greetings, I recently have had a horrible experience losing about 40 scarlet hermit crabs on two separate occasions.  The hermits were added just after cycling the tank. <This could do it>   The symptoms before loss was extremely unusual -- complete stillness for a period of time, and then crawling out of their shells with no apparent signs of distress, <! Crawling out of shells, stillness are apparent signs...> climbing around (usually upward) for a time, and eventually dying without ever going back into their shells.  The first time I had a huge loss I found out that my water had an unexplained nitrite spike.  (Unexplained because there was no ammonia spike before that -- I had been testing daily). <...>   I believe that the new saltwater I'd been mixing up is the problem (as it tested at .5 in ammonia upon mixing), and changed salt mixes.  But a few days later I had a second die-off.  After testing my water quality, the ONLY thing wrong with the tank is that the alkalinity was outrageous. <Also toxic...> Like someone who didn't know better, I'd been trying to combat my continuously dropping ph by adding buffer about every other day. <How?> I'm told that this caused me to have a high alkalinity.  Is this fatal to hermits? <... yes> I also lost my peppermint shrimp on the second occasion I lost a bunch of hermits, but the ghost shrimp in the tank were not affected.  Do the symptoms I mention re the hermits sound familiar? <Oh yes... as you would know had you followed directions before writing us and read what is already posted...> I'm told it is extremely rare for them to leave their shells. I have stopped using buffer and am still battling a low pH, which remains about 7.9 to 8 no matter what time of the day I test (morning and night).   My substrate is aragonite ("live") from Petco.  Right after doing water changes without buffer to decrease the alkalinity, the few crabs I have remaining got more active and are doing fine, despite the lower pH.  Did I read on here that new substrate can affect pH in a negative way? Thanks for your help! Emilie <Have just skipped down. Please start reading here: http://www.wetwebmedia.com/hermitdisfaqs.htm and the linked files above... "But wait, there's more!"... Keep reading re the other issues you have questions re above... the search tool, indices... BobF>

SW source, LFS?   8/12/06 Hi, I Was Wondering If Aquarium's Will Sell Salt Water For My Sea Hermit Crabs? -April <Many do... or the means for you to make your own. Please read here: http://www.wetwebmedia.com/seawater.htm and the linked files above. Bob Fenner>

Hermit Crabs/Systems   8/11/06 Hi <Hello April> I brought home 2 hermit crabs from out of the ocean in Ocean City, Md. I also have 4 land hermit crabs already. Do the ones I found in the ocean have to be kept in salt water? <Yes> If they don't, can I eventually put them in with the land crabs? <No> Do the ones in the ocean eat the same food as well? <All crabs are scavengers and will eat most anything.> Thank you, <You're welcome.  In future queries, please do a grammar/punctuation check so we do not have to do it.  Just do not have time to edit.  Thank you, James (Salty Dog)> -April

Quick question about my hermit crabs behavior 01-26-06   I tried finding the answer to my question all over your site and the web but came up short so you're my last option.  I have a 50 gallon salt water reef aquarium and recently (about 2 weeks ago) introduced 5 hermit crabs to the tank.  Not sure on the species?  However about a week ago I noticed that the crabs had produced some sort of whitish colored substance around some of the food that I feed the fish, that ends up on the bed of the aquarium.  Afterwards I saw that on top of this whitish matter a aggregation of pink matter began forming on the top.  Is this some sort of harmful substance that might kill off my fish, coral, and anemone?  Is the pink matter bacteria consuming the food locked within?  Thank you for your help. <Don't be too hard on your hermits. This is not their fault, it is yours... What you are witnessing is a bacterial break-down of excess food. You will want to cut back your feeding or target feed your fish better to eliminate this problem. Travis>      Sincerely   F. Sokhansanj

Coldwater Hermit Crabs in a tropical arrangement? 10/31/05 Hello WWM Crew, I have a 25 gallon SW tank. Currently the tank is set at 78 degrees. I was wondering if a coldwater hermit crab species could live in my tank. I live in Monterey, California where there are many local tidepools that are occupied by many hermit crabs. I've looked online and the hermit crab species is Pagurus samuelis. I figured that since they are tide pool dwelling animals they are acclimated to frequent changes in their habitat,  <Good point> such as temperature, so they may be able to be ok at 78 degrees. What is your opinion? Thanks, Taylor. <Might adjust... if tried/introduced during the warmer time of the year... but don't think these will live well or long kept in a tropical setting. Bob Fenner> 

Mystery Hermit Crab Help - 10/20/2005 Hello.  Your website has the most in-depth info anywhere on the web!   <Hefty accusation there, Mary!  I'm glad you find the site useful.  Sabrina with you today.> You are all to be congratulated on your time, effort and expertise!   <Thank you very, very much for these kind words....> I'll try to watch my language. <Ahh, good.> That said....  I, like others, ended up bringing home a couple of hermit crabs by mistake from Dauphin Island. <Uhh, yikes.  Please, please folks - if you pick up trinkets at the beach, make sure the animals that used them are done with them!> They had survived more than 2 weeks in a tied plastic bag with other empty shells; traveling from southern Alabama up to and through the Smoky Mountains (all of those elevation and temperature changes, whew!) and finally to northern Kentucky.  So I figured the very least that I owed them was my very best efforts to help them live.  I knew absolutely nothing about them and had trouble at first figuring out that they are NOT the hermit crabs that you can readily find info for on the web and that so many kids keep as pets.  I haven't been able to exactly identify them, but here is a link to a picture of them:  http://www.touchthesea.org/hermitcrablv2.jpg <This is an aquatic or semi-aquatic animal, to be sure.  Not just a land hermit, as you correctly guessed.> I set up a mini (10 gal) salt water aquarium with:  Aragonite Reef Sand, other shells that I brought home (some of which may be suitable future homes for them), salt water made with dechlorinated tap water and Instant Ocean Sea Salt, mixed appropriately, and a thermometer. <Heater?  Filtration?  Testing supplies?  Food?> Yesterday, I thought they were goners.  After setting this 'system' up and putting them in, I gave them some food choices that I had tried previously like commercial pellets, leaf lettuce, "Sea Weed Salad, Green Marine Algae" and covered the whole she-bang with a towel and left them undisturbed overnight. <I would try offering small bits of thawed frozen raw human-consumption shrimp....  and remove in a few tens of minutes if left untouched.> (In Kentucky, I think 'she-bang'  is a noun, LOL)   <Can double as a verb in Kansas, spelled 'shebang'.> And, alas, they seem to be very happy crabs this morning !! SO, I will go ahead and install a water pump and filtering system, the information for which I can get from your FAQs.   <Great.> But, FINALLY, here is my question.... I have yet to see them attempt to eat anything that I have offered and I am stumped.   <These opportunistic dudes prefer meatier fare....  Try shrimp, krill, even bits of human-consumption fish.> Today, they seem to be filtering the water through their mouths and maybe eating the algae that came in the sand??.   <They'll pick through it some, sure.> But that won't last very long, will it?   <No.> What else can I offer them to eat?   <As above.> Do they maybe just need more time to acclimate to their surrounding? <Perhaps.> Minerals? <Regular water changes with saltwater of the correct salinity using a quality salt mix will help with this.  You may wish to start testing, maintaining calcium and alkalinity.> If this is successful, I think I just might invest in a new hobby.  I currently am husband to a 40 gal FW aquarium that has been very successful over the years.    <Must've been tough to get THAT marriage license!> A Marine tank would be too cool !  I had always been intimidated by the science of one, but no longer, thanks to all of the efforts y'all put into this web site. <Glad we could be of service.> ('y'all' is definitely a noun in KY !)   <That's one I could never get the hang of.> I look forward to some suggestions on food, minerals, etc.  Keep up the great work, so many of us appreciate it. <And again, thank you very much for these kind words.  It means a great deal to see comments like these.> Mary Robben <Wishing you well,  -Sabrina>

Drum noise and marine hermit crabs  09/13/2005 Hi Helper Guys!     My grandson has a huge drum set in his small bedroom, and a ten gallon aquarium 2 feet away, on a stand.  He had about 20 fish that quickly died, and our local pet store fish expert said it could've been heart attacks from the extremely loud noise from the drum set.  I had the water checked a few times a week at the pet store, and it was usually fine. Once it barely registered bad so I did a water exchange until it registered good. They were regularly fed, too.  There are still 2 sucker fish in the aquarium that are alive, but the pet store said they are very hardy and have thicker skin.     Anyway, now he wants to put marine hermit crabs in the aquarium, and we were wondering if the same thing will happen to the crabs when he plays his loud drums.  Thanks so much for your help. The pet store said the crab's shells would protect them from the noise, but I'm not sure that they really knew the answer, and so I wanted an expert's opinion. <Vibrations will and do cause undo stress on aquatic animals.  James (Salty Dog)>                                                 Coreen Bousfield

Jumping' In With All Ten Feet:  From Land Hermits To Marine - 01/17/2005 Howdy! <Ahoy, thar!> I've just spent two hours reading your site and can't find an answer to my question, so I guess I'm an oddball (well, I know I'm an oddball, apparently I'm a unique oddball!) <Ahh, we're ALL unique oddballs.  No worries.> I keep quite a few land hermit crabs as pets-last count was 43 in five species- <Err, and I thought *I* had a few too many, with 14 of 4 species.... <grin> > and I spotted some tiny blue legs yesterday.  I'd love to get a couple, but I can't seem to find much in the way of info on keeping just crabs. <Lots of folks do so, in "Nano" reef aquaria that are simply too small to comfortably house fish.  Mostly, though, the knowledge required is the same as for any marine system.  I know I've tried to post some info on a couple of hermit forums, but it has been largely disregarded....  Sigh.> Are they only kept as cleaners, or are they ever kept by themselves? <Either way.  To be honest, Bluelegs aren't the friendliest cleaner.  Lots of folks like them.  I prefer the scarlet reef hermits - much less vicious, IMO/IME.> If I can keep them alone, how much tank space would I need for two blue legs, say, 1/8" (yes, I'm fully aware that they will grow and I will need to upgrade later) <Oi.  I wouldn't dare do just two, or you'll end up eventually with just one.  With your experience in land hermits, I'm sure you're familiar with "shell fights" - Bluelegs take these to the next level....  Gladiators fighting to the death were never so aggressive as these critters can be.  Again, just my experience, but they tend to tear each other apart if they don't have MORE than enough shells and lots of distractions.> I'm trying to get an idea of what would be required before I take any home! Thank you SO much for your time and your willingness to help raw newbies! <Ahh, some very basics....  To be honest, I would strongly urge you to aim for a tank of 20 gallons or more.  A smaller tank will be MUCH harder to keep stable....  really, I can't tell you how much easier a 20 is than a 10.  Please, please, take that into consideration.  Now, if all you want are hermits, this is going to be pretty easy.  I would urge you to use "live rock" in the tank - most often, we recommend 1-2 pounds of rock per gallon, but you can skimp on this and add a few pounds at a time (just make sure it is "cured" before adding, read through the articles and FAQs on live rock for more info).  You'll need a quality marine salt.  "Doc Wellfish" or other salts marketed for freshwater aquaria simply won't cut it.  A hygrometer is of great importance - keep the water at a specific gravity at 1.024-ish.  I would like to recommend that you invest in a decent skimmer, but with the cost of such an item, I just don't think it would be worth it for your applications.  For substrate, you would probably do best to have less than one inch of sand, preferably aragonite.  Crushed coral will do, but sand, IMO, is a much better substrate.  Also, the Bluelegs will not dig into the substrate to molt like the land hermits do.  Nor will other small, semi-peaceful hermits.... or any marine hermits that I know of.  There is really a LOT of information to soak up before you take on this endeavor - but you are most definitely capable - I would urge you to read the following article:  http://www.wetwebmedia.com/nemoproart.htm  - this article is geared to would-be "Nemo" keepers, but nearly all of it applies to your project, as well.  I especially like the list of equipment needed, but would like to stress NOT to use an incandescent light fixture, which can overheat such a small tank.  Also, I would urge you to visit our forum at http://www.wetwebfotos.com/talk and ask questions and gather information there, as well.  You will find me there as "vintage_fish".> Also, just a couple comments about your land crab pages: You have almost everything down pat, especially with sending people on to hermit-crabs. COM or landhermitcrabs.com. However, land crabs tend to do best in groups, and they need their water dechlorinated; also, they are very sensitive to metals and need high humidity, so wire cages don't work very well. <Agreed wholeheartedly on all of the above.  Please understand that much of that area of our site is rather outdated.  Perhaps someone will get around to placing an up-to-date article there, some time soon....> Again, thank you so much for your time and attention! <And thank you for your interest in what is most certainly a very extensive and exciting hobby!  Please do read that article, to kind of get a feel for what you need to know and do, and make use of our forums - and if you have any further questions, PLEASE feel free to write in again!  We're here for this very reason. Sarah <Wishing you and your future Bluelegs well,  -Sabrina>

Hermit Crab Habitat Hi, <Hello Grandma Bonnie> My grandson has gotten a marine hermit crab from Florida. We do not have a saltwater fish tank, but I got a big plastic Tupperware container and I filled it with saltwater made from Instant Ocean salt and I used Start Right to remove all chlorine and such. I made it about an inch deeper than his head when he walks around. We put three more shells in there for him, a couple fancy oyster or clam shells, some painted coral, a dead sea sponge, a lava rock, and a (bird) cuttlebone for calcium, that we weighed down with the lava rock. I figured we would feed him once a day in another smaller container (with water) for an hour or so till he gets done eating, then put him back in his other living container to help keep it clean. And maybe change the water in his living container once a week or two weeks. Would this be sufficient? <I think so, hermits are very hardy creatures.> Or I was wondering if he needed an air tube in the water for oxygen or not? <It isn't necessary, provided there is just the crab.>There are no fish with him. Just him alone and we had him for one day and he switched shells already. I heard this may be common. I'm mainly asking about the air tube, I don't want to suffocate him, or if you see anything else we might be doing wrong.  <You should be fine.  James (Salty Dog)> Thank you,  His Grandma Bonnie

Scarlet Hermit Crabs Hi CREW, <Hello Debi>  I understand Scarlet Hermits need to go looking for a new shell as they grow. <Correct>  So how many empty shells should I provide and where is it best to place them to assure happy hunting? Is it ok to get shells from a shell shop as long as I boil the empties before putting them in the tank?  <Four or five empty shells should be enough. Choose various sizes that are slightly larger than the home he is in. I believe shells from a shell shop would be OK. You want to pick shells that are similar in shape to the one he is in now. I would not use any if they were sprayed with a clear coat or anything like that. James (Salty Dog)>

Help - a killer in my tank - hermit crabs MIA Dear Crew <Peter> I have been reading your site for some time tonight, but ... ... who has been eating my small blue legged hermit crabs? <Ooooh, I do so love a mystery!> I shone a light in the tank late last night and saw only two  2-3" long, dead straight, spaghetti like feelers. After a few seconds in the light the feelers slowly spiraled away into the rock. <Mmmm, maybe the Polychaete worm butler "did it?"...> Is this fascinating or nasty and should I dump that piece of rock?<Hello Peter.  Do not dump the rock.  The worms are probably innocent.  Your hermits are probably in a rock crevice eating trapped food particles>  James (Salty Dog) <Oh... I see our new Crewmember James has answered your query...> I need help with this one.  I am new to the hobby, and did not realize what goes on after the lights go out. Thanks a lot. Peter Hosier <I agree with Salty... let some time go by... and if you can, continue to monitor that worm, other possible hitchhiker predators and consider baiting, removing them. Please read here: http://www.wetwebmedia.com/polychaecompfaqs.htm Bob Fenner>

Hermit Crab Genocide? Dear WWM,     I always start my emails with a thank you for all you're doing.  So, once again, thanks! <Welcome> As I am about to discuss the health (or lack thereof) of my hermit crabs, keep in mind that all my fish are doing fine, and that Am, trites are at 0, trates are minimal, SG and pH are fine. <Okay> Anyway.  My 2-month-old 30-gal SW aquarium cycled beautifully with Live Rock, two weeks after which I added two paired clowns.  Two weeks thereafter I added a royal Gramma (who had a bit of an adventure getting into the tank, jumped out of the transition container and onto my carpet), but after a few days in hiding, he's now king of the tank, not at all shy, and gets along with my clowns.  I decided to add some sand sifters... my LFS recommended I get 5 red-legged hermit crabs.  They assured me these guys were very hardy and did not need to be QT'ed or acclimated.  The crabs did fine at first.  They were all very active, constantly going through my sand and climbing through my LR.  A while later, my LFS recommended I add Calcium and Alkalinity to my tank to make it suitable for corals.  Well, ever since I added these two components, my hermits have slowed down considerably.  They don't move around any more. <Good observation>   I thought they were dead, but when I look closely, their little "antennae" (or whatever they have between their eyes) still move around.  However, one of the crabs, I found this morning, sprawled out on the sand, out of his shell.  I'm not sure how much of a body they have besides the red legs that we see when they're in their shells, but this guy did not have much of anything left besides his legs.   <There is not much to these anomurans> When I tried taking him out of the tank, his legs separated from each other!   <Uhh, dead> I'm baffled as to what happened to him.  It almost looks like the rest of his body was eaten.  Is this guy's decision to crawl out of shell in any way related to the deterioration in activity of the other crabs? <Not likely... very likely due to the alkaline reserve and calcium addition/s> Is it possible these guys' health was anyway going downhill and coincided with me adding the two components?  Or is their health downturn directly resulting from the chemicals? <The latter> I liked these guys, too. :( Your responses are, as always, greatly appreciated. Paul Ghica <Please read here: http://wetwebmedia.com/hermitdisfaqs.htm and on to the Related FAQs (linked, above, in blue). Bob Fenner>
Re: Hermit Crab Genocide?
Thank you for your responses, Bob! <Welcome> I decided to discontinue my Alkalinity and Calcium treatment of my tank for the sake of my hermits. <A good idea> Now, the story below comes with a twisted development.  I thought one of my 5 crabs died.  I saw his shell-less body sprawled out on the floor of the aquarium.  The same thing happened to another one of my hermits.   Body on the floor.  Within two days, it was broken apart, presumably eaten.  That should leave me with 3 hermits, right?  However, I just counted 4 crabs crawling along today. <Hee heee! I smell a molt>   All 4 that I saw were pretty big, so that rules out the possibility of a baby.  Two of them were still pretty motionless, except for their little antennae moving around... now, the other two have gotten simply huge, have seemingly almost outgrown their shells, and are quite active, climbing anything they possibly can. I'm starting to think that those were not crabs I saw on the floor, but just their molts (is that what they're called when they "shed"?). <Yep> My apologies in advance for any poor terminology I may use.  I still don't know where to find the elusive 5th crab, or his shell.  Is there anyway to make my tank reef-ready (my LFS insists I must add Alkalinity and Calcium in order to do so) without further endangering my hermits?  It seems their health and activity is directly related to my adding the chemicals. <Best to not add anything at this point.> Now, of the four I currently see inside in the tank, is there a correlation between the fact that two are bigger and active, two are still small and inactive, and that there are two molts on the floor? <Likely the larger ones are growing faster... do make some assortment of shells available for their use> If there might be some link, which two are most likely to have recently shed?  The active ones, or the inactive ones? <The active> The reason I ask is because if the active ones are the ones whose molts are on the ground, perhaps I can look forward to the others molting and becoming bigger and active.  If the inactive ones are the ones whose molts are on the ground, I'll  presumably need to do something before my two remaining active crabs meet the same comatose fate. <Yes, they all will molt... every few months... slower with age, larger size> Thank you for sharing your wealth of knowledge. Paul Ghica <Glad to share. Bob Fenner>

Vacation Crab Bonanza Hi,<Hi, MikeD here> I have a purple pincher hermit crab and my niece found some hermit crabs on the beach she wants me to have. I had mentioned to her that I wanted another one to keep my purple claw company. The thing is that she found these in the salt water. I don't want to break her heart, but I have no idea how to take care of these. I don't know anything about them. Do I keep them in the water all the time and if they are ok not to keep in the water then, are they ok to put in the same tank as my purple claw one<Unfortunately, no, these are marine vs. the apparently land species that you have>. I am still learning how to take care of the one I got. I need to know all the basics of taking care of the salt water ones<"all of the basics" is probably a lot more than you're prepared to deal with at the moment.>. There is like 30 of them that she's giving me<Yep, that's more than you're prepared to deal with!>. How do I take care of these...are they any different then the one I have?<In appearance, no, in requirements they might as well be Martian crabs> If I have to keep them in water the whole time, then are they ok with fresh water<NO!> or should I get the same water salt to put in the water? Do they need the calcium powder and how cold should the water be? Any information on the ones from the beach water is helpful.<My honest suggestion is to call your local pet shops that handle marine fish and see if they'll help you out. Although crabs are less demanding than fish, you'd still need an established marine aquarium that's been up and running for at least 6 weeks, and frankly, you just don't have the time, no matter how willing. The type crabs your niece has brought back are actually much sought after by intelligent salt water shop owners as they are likely larger than the type they can often purchase through normal channels.>>

Hermit Crabs We went to Shinnecock Canal on Long Island, and my son wanted to bring home some hermit crabs. << I'm not a big advocate of bringing things home from the beach.  Sometimes they are more difficult to care for than we expect. >> We have about 30 of them (they are pretty small) in a 1 gallon fish bowl with a little gravel and the salt water we brought them home in mixed with a little fresh water. << That is a lot of crabs in a little bowl, I would be sure and change water often. >> But how are we supposed to take care of them...environment...food...shells? << The best thing for them is rock and algae.  I wouldn't worry about shells yet, I'd worry about keeping them alive in such a small tank.  Actually, I'd look at getting a bigger tank.  Otherwise you are stuck trying to keep the temperature the same, and the water clean.  As for food, I would think they would eat Nori, which is seaweed you can buy at most oriental food markets. >>   Even though we found them in saltwater will they live in fresh water?  << They may, but far better to replicate their environment the best you can.  Also, with such a small bowl mixing up saltwater would be easy.  You can do a 50% water change and that is only 1/2 gallon. >>   I would appreciate all they info you can give me.  Thanks,  Jenn. << Hope that helps. >> <<  Adam Blundell  >>

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 some 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...>

Hermit crabs hello there Robert, I would like to know If It is possible to keep cold water hermit crabs permanently in a tropical reef set up. I stay on the west coast of Scotland where I would be collecting my specimens. I have a 50 gallon tank with various soft corals. <Hmm, well, sometimes these cold water non-vertebrate animals will "make the switch" to a degree collected during the warm months of the year... And species that are intertidal are pretty eurythermal... About the only way to tell my friend is to collect and try some out. Bob Fenner>

Hermit crabs hi there are a lot of hermit crabs just in the bay down from my house I was wondering if it would be alright to put them in my tank do some hermit crabs need air because these hermit crabs are always in the water when I see them but in shallow puddles because I wouldn't want to drown them or anything <You are a good observer... many hermit crabs are much more amphibious than totally aquatic. Do provide a small area for these to crawl out of the water. Bob Fenner>

Crabs Hello, back again! It's so nice to know that when I post a question, it will be answered! This service is highly needed today and I am delirious each time I get the chance to use it!. Also, that Steven, is FUNNY! When Robert was out he sure came up hilarious scenarios for his absence! <Thank you for the compliment, but I think you meant Anthony. He was the one coming up with the truly hilarious reasons for Bob's absence. I was only moderately amusing.> So I just wanted you to know, that although I may appear to be casual in my need for info, I appreciate it so much!! It makes this hobby so much more possible when you have almost instant answers! Now, to my question,..............hmmm, I forgot it! Oh yeah, last summer I went down to our local beach, (I live on Cape Cod) and collected about 20 little hermit crabs. They were taken from the small pools that form along the beach when the waves come in. Seeing that this water was always very warm, I figured they would do nicely in my reef tank. Oh contrary! It appeared they WERE settling in nicely for about the first 3 months. But then I noticed that their numbers were dwindling. I wasn't sure if they were hiding or what, but now, about 5 months later, I haven't seen a single one! All I have in my 55 g. tank is 3 dominos, 2 yellow tail blue damsels, 2 camel shrimp, and 1 coral shrimp. I don't think THEY would be eating them. Can you tell me why they would die off? Also, was it illegal to take them from the beach? I see little kids do this all the time, and I have not yet seen the "Crab Police" stop them at the gate! I really hate to pay 3 dollars a crab at my local shop when I can get them for free! <As you discovered, these little guys are a temperate species and while the water was warm at the time, these crabs needed/were use to it getting cold and their numbers dwindled when it stayed hot. You would be better off buying the tropical variety from your LFS. I prefer the so called scarlet reef hermit crab.>Thanks guys! Pam <You are welcome, Steven Pro.>

New Hermit Homes I am new to saltwater tank keeping so please bare with my questions. <You are welcome here> I have a red legged hermit crab, he is very small, about a half an inch. I have read on your site (which is awesome, I use it all the time) that I need to have a larger shell available for him to "move into". When should I have this new shell available for him and where can I find a suitable new shell? Also, how much larger should the new shell be? Thanks for any help you can provide. <A good idea to have a few "other" shells about for "up-sizing" all the time. To assure these are "marine safe" I suggest getting a few from your local fish store, or e-tailer... in an assortment of just barely larger on up to about twice the size your Hermit currently occupies. Bob Fenner> Theresa

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>
Re: Snail & Hermit Crab waste
Hi Steve: I have a 54 gallon corner tank. I guess I should pull out some of the crabs and snails. What do you think? <Yes, I would remove all but two of each hermit crab. I would leave all the snails and if you need more algae eaters, get ten more Astrea, Cerith, or Nerites snails. I like to use a variety of snails as they all seem to prefer to eat different things. -Steven Pro>
Re: Snail & Hermit Crab
waste Thanks Steve, FFExpress should redo their Web Site about adding the correct amount of Invertebrates. ~Aram <Nothing in particular about FFExpress, but all of these places are in the business of selling. I never assume any salesperson, selling anything, knows everything about their product or wants to be my friend. Pet stores are all businesses, too. Just approach them as you should any business, as an educated consumer. -Steven Pro>

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