FAQs on Terrestrial/Freshwater Hermit Crabs Systems

FAQs on Terrestrial/Freshwater Hermit Crabs Systems

Related Articles: Terrestrial Hermit Crabs, Freshwater Crustaceans, Invertebrates for Freshwater Aquariums by Neale Monks,

All so-called "freshwater" hermit crabs are actually amphibious, and as such, unsuitable for use in an aquarium. The only truly non-marine, fully aquatic hermit crab in the trade I'm aware of is Clibanarius tricolor, the blue-leg hermit crab. It does very well in brackish water aquaria at SG 1.010+. It cannot be adapted to freshwater. Cheers, Neale.

tiny crawlers, assoc. w/ terr. hermit 10/4/10
Two days ago I purchased a hermit crab for my child. To our surprise, the hermit crab had company today! There were tiny worms in the mulch-like substance that was recommended for the tank. I thought they may have been bristle worms( I know that they sometimes buddy up with hermit crabs in their shells), but your many descriptions do not match what these appeared to be. They were approximately 1/4" long and light brown in color. They resembled a very small earthworm. I apologize for not having a picture. I panicked, and dumped them. There were at least three of them. Do you have an idea of what they were? My next question is, "Are they harmful to the crab or my child?" Thank you for your time.
<In the mulch... Very likely these are/were not actually worms of any sort, but insect larvae... And other than being noisome, likely not harmful to your child. Bob Fenner>
Re: tiny crawlers 10/5/10
Thank you
<Welcome!>

Hermit crab advice for classroom care 9/7/04 Dear Mr. Fenner, <Anthony Calfo in his stead> As new hermit crab parents, we were very impressed with your website and we learned a lot about how to care for our hermit crabs (Dion, Duncan, Lucy, and Henry). We are also new teachers and our hermit crabs will be our class pets. They will be living in our classrooms. We read that they must be sprayed daily with water, <yes... very important for their good health... even breathing> but we were wondering what we should do on Saturday and Sunday when we are not in our classrooms. <hmm... they will survive. But do spray them well weekdays without fail... particularly Friday and Monday of course> <<RMF would place a damp sponge in their system... re-wet it daily>> Also, should they be fed daily as well, or is it okay to leave extra food on weekends? <less is better in some cases... avoid feeding heavily. A few times weekly is fine: Monday Weds and Friday> Is it possible for them to survive without our care over the weekend? <yep... no worries> Please respond ASAP as school is starting on Thursday. Thanks for all your help! Sincerely, Candice and Sarah ( <with kind regards, Anthony>

Help. Terr. Hermit crab beh., rel. matters 7/9/10
we have had hermit crabs for over three years, we have seen them naked but this time one went naked and climbed into the water dish, and what we started to think he was molting. He hasn't moved or done anything for 5 days. He was moving just a couple of days ago. But nothing, we had to remove the water dish because the other one was trying to get at it. I don't smell anything. Would this be consider molting? If so, how long?
He is very small. He has molted before but never on top of the surface.
thank you
<Greetings. It isn't normal for Hermit Crabs to moult outside of their shells or at least outside some sort of burrow, so if you see your Hermit Crab moulting on top of the sand or coir, something is probably amiss.
Start by checking diet, particularly the availability of iodine, as iodine deficiency seems to be a very common reason for improper moulting. Note that Hermit Crabs can be cannibalistic, and it is crucial that recently-moulted Hermits get themselves into shells as fast as possible. If that isn't happening here, you need to separate them. The fact your Hermit hasn't moved is very worrying, and I'd be isolating him regardless. Make sure the vivarium is suitably warm -- unless you're in the tropics room temperature won't do -- and sufficiently humid. Like a lot of cold-blooded animals "dying" can take months, even years, so just because you've been successful thus far doesn't mean you've actually been keeping them properly. Sometimes it takes a long time for the problem to become fatal.
So sit back, review living conditions, and make sure you're providing everything you should. Most of the people selling Hermit Crabs in malls and whatnot haven't the foggiest idea what they need, and those little plastic habitats they sell are pure garbage. At minimum, you need a 10 gallon aquarium with a couple of inches depth of damp sand or coir, plus a shallow basin of either dechlorinated freshwater (for Purple Pincer Crabs, Coenobita clypeatus) or brackish water (for Ecuadorian Crabs, Coenobita compressus) depending on the species you're keeping. This is VERY important, and if you provide the wrong type of water you will create problems in the long term. Unfortunately both species are equally available, and the retailers, particularly those in malls, have not a clue which one they're selling. Place a heating pad under the tank to maintain a steady 25 C/77 F. You need a hood to keep humidity in the tank, but sufficient ventilation to prevent fungal infections. You need to clean the sand or coir regularly, ideally every couple of weeks. The diet should be varied but calcium-rich, so lots of things like whole lancefish and unshelled shrimps rather than just prawn meat or fish fillet. Some vegetable matter, such as banana, is also important. An iodine supplement is almost always required, though some Hermit Crab foods may include iodine -- check the labeling. I hope this helps. Cheers, Neale.>

Hermit crabs friend or enemy 3/24/10
Good afternoon,
We purchased 2 hermit crabs about 2 years ago. Both have molted once.
However when crab A molted a second time crab B attacked it. I looked at the cage and saw that crab B ejected crab A from his shell. We separated the crabs and crab A survived. After 4 weeks we reintroduced the crabs
together and crab B immediately moved to what looked like an attack of crab A. Crab B came with its large pincer out and basically charged crab A. Everything we moved crab A and crab B apart, crab B charged crab A. Are
they now enemies? I plan to keep them separated; is this the right thing to do? Can crabs that once lived together peacefully for almost 2 years not get along after being separated?
Thank you
Jonathan
<You don't say whether these are marine, freshwater or terrestrial hermit crabs, but in general, yes, all hermit crabs fight over shells. This is widely observed in the wild because whole shells are a limited resource, and there are more hermit crabs looking for shells than there ever are enough empty shells. So there's some survival of the fittest going on! Make sure you have adequate empty shells *of the right sizes and types* of the hermits you're keeping. Normally aggression between specimens is minimal if they have enough shells to choose from. If they're fighting, chances are you don't have the right shells or enough of them. Cheers, Neale.>
Re: Hermit crabs friend or enemy 3/24/10
Good afternoon,
Thank you for your very prompt response.
<My pleasure.>
They are both terrestrial crabs.
<Okay.>
I learn something new everyday. To my eye crab A and B are in the same size shell- but I guess crab B sees something in Crab A's shell that he wants.
<Guess so!>
We will get some new shells and see what happens.
<Good.>
For a follow up question- Crab B has not molted a second time and I think he is overdue -b/c crab B molted before A the first time and A has already molted second time and crab B's color is "washed out". Can crab B getting ready to molt but he will not b/c he cannot find the right shell?
<Terrestrial hermit crabs need something to dig into before they can moult.
Slightly damp moss or coir are recommended for this. They also need to drink a lot beforehand, because the water is used to pump up their bodies and so crack the old skeleton. If your crab is drinking a lot and digging a lot, that's a good sign moulting is around the corner. Before moulting happens, isolate the moulting crab if at all possible: crustaceans can be remarkably cannibalistic towards one another if they find some poor crab that's just moulted! Without a separate moulting tank, hermit crab keepers usually end up with just one specimen. In any case, leave the moulting crab alone while it is moulting, and be sure to let the crab eat its old skeleton. After moulting the now-larger hermit will go looking for a bigger shell. Moulting should take place every 1.5 years, and to moult properly
the hermit needs a good, calcium-rich diet (unshelled prawns, whole lancefish, etc), particularly in the weeks leading up to the moult.>
Thank you and thank you for your insight
Jonathan
<Cheers, Neale.>

What's wrong with them? Hermits, terr.... sys., fdg., beh.... 8/5/09
Hello, my name is Ben.
Sorry to bother you, but there is something that's really bothering me and I'm worried about my Hermit Crabs.
<Interesting pets, and not difficult to keep, but often trickier than the sales clerks suggest. Suggest you visit one particular site that's all hermits, all the time:
http://hermit-crabs.com/
It's a good site, and very frank about what's needed to keep them healthy.>
My brothers and I bought 3 hermit crabs (sorry, not so sure about the species) at Petsmart two days ago, we also bought frog moss, sponges, 3 shells of the appropriate size and some decorations. I had everything else ready at my house, hideys, chlorine remover, dishes, and bag of play sand.
I didn't buy any salt, though.
<Ah, this does matter. There are at least two species equally commonly traded in the US: Coenobita clypeatus, which needs a freshwater bathing pool, and Coenobita compressus, which needs brackish water or seawater in its bathing pool. Now, the critical thing to remember is that both species are widely sold, and sales clerks will say that both species need freshwater. That helps them make their sales quota! So do not, repeat DO NOT, take on trust any statement that the Hermit you have is a freshwater species. Review the link below, and confirm for yourself.
http://hermit-crabs.com/species.html
Use marine salt mix to make up the brackish water should you need it. At the amounts you're using the cost will be trivial, but you'll regret using cooking salt, aquarium tonic salt, or anything else that wouldn't be used
in a marine aquarium. You're after brands such as Reef Crystals, Instant Ocean, or whatever the cheaper generic marine aquarium salt is at your pet store.>
The lady who helped us mentioned something about them having only freshwater hermit crabs in store and that salt water was not necessary. I also didn't buy any commercial food, they didn't have any in store and I
heard they can a lot of other things instead.
<Certainly, these crabs are entirely omnivorous. An ideal diet would include soft fruit, freeze-dried or wet-frozen krill, squashed cooked peas, and chunks of lancefish, which you can buy frozen at pet stores. Lancefish are small fish, a bit like whitebait, and because they contain bones, they're a good source of calcium.>
I've fed them daily, watered the moss, misted the tank, gave them water.
(I've made sure to always use the water I setup with drops of chlorine remover every time I use any water)
<Very good.>
Well, here's my problem, I don't think they've eaten since I got them 2 days ago. I've fed them apple, melon, carrot, with small dabs of peanut butter or honey. I haven't really seen any change in the food from when I put it there. So I'm worried whether they're eating or not? Why not? How long could they go on like this?
<It is actually very common for Hermits to "go quiet" when first introduced to their new habitat. They're also somewhat nocturnal in the wild, and become more day-active once they settle down. So, between these two factors, you might well not see very much for the first couple days, even a week or so. Provided your Hermit is still alive, I wouldn't worry unduly about a quiet specimen for at least a week or so after purchase. Remove uneaten food to prevent fruit flies, fungus, etc. A small piece of lancefish would, I bet, be the thing to get them eating, so try that one night. Dead fish are a real treat in the wild, and land crabs get very
excited when they smell one!>
I also haven't seen a lot of action from them. Of course I'm not aware of what goes on after I fall asleep, but when I'm awake, they mostly hide all day. At night we take them out to play and exercise them a bit since
they're nocturnal but they don't seem to trust us much.
<They won't. It takes weeks before they become "trusting".>
It takes long for them to come out and when they do they try to scurry in the opposite direction, we always try to be as gentle as we can. Please, could you give us some tips that could help us earn there trust?
<Time.>
Please, I'm afraid they'll die, I've had hermit crabs before, but I wasn't well informed or prepared the first time. This time I did research on everything before getting them and I was prepared, but I don't understand
why they aren't eating. Thanks for taking time to read this, and I'm sorry to have bothered you.
Thank you,
Ben
<Do read the site mentioned, identify the species you have, adjust the salinity of the bathing pool if required, and give your Hermits time to settle down. Remember they need warmth, and if your habitat is too cold
(air temperature less than 22 C/72 F) they're not going to be active at all, and will probably die quite quickly. These animals live in the Caribbean area, so if you don't live somewhere with a similar tropical
climate, you WILL need a heater. An undertank heating mat is ideal, and doesn't cost much. Alternatively, some type of heating lamp could be used; not a regular lamp, a proper heating lamp mind you! Visit a reptile pet store and review the options for heating lizards, snakes and other warmth-loving animals. All of these tropical pets need heat, and it's a shame sales clerks often suggest they can be kept at room temperature in
the US and Europe; they very largely can't. If you happen to live somewhere warm like Florida where the air temperature would be adequate, don't forget that air conditioning will cool the air in your home, and that will also cool the air in your Hermit habitat. So do think very carefully about heating: it's probably the single most common reason why tropical "critters" of all kinds die in captivity. Cheers, Neale.>

Hermit crab hiding spot, terr. -- 07/01/09
Hi, my son loves his new little friend, Hermie, who is a bit shy, so we purchased a small, hollowed-out half log called a Pet Refuge by Mac's Creatures & Critters of Murphy, Oregon, from Petco. The problem is, I
cannot find any information about which type of wood this refuge is made from, knowing that evergreen-type woods are not good for hermit crabs. Do you have any familiarity at all with this brand?
Thanks,
Krishna
<Only from what I see on Petco.com's site... However, I worked for the co.
(as a consultant and buyer) for three years... and was just visiting corporate/DC 100 last week... and know the company to be ethical... And very responsive to direct queries... Do write them/Petco and ask directly;
or for "Mac's" address (don't see via the Net) to contact them re. Bob Fenner>

Re: Hermit crab hiding spot 7/2/09
Will do, Bob. Thank you very much for your quick reply.
<Certainly welcome Krishna. BobF>

Hermit crabs 11/10/08 Hi! My little sisters and I have pet hermit crabs. We put them in one tank. There are no bugs in it, but for some reason when I looked in the tank today, there was a web across one of the shells with little black dots in it. Is it from the crabs? Do you know what it is? <Greetings. It is possible I suppose that these webs are spider webs, or silk webs spun by something else. In that case, they won't do any harm and can be rinsed off with some clean water. But I'm a little more concerned that these webs might be in fact fungal hyphae. Fungi will grow on anything that is organic, warm, and damp. Hermit crabs need to be kept warm, as you know, since they're tropical animals that quickly die if they are kept at room temperature. But they also need a well ventilated environment. Usually these two things are taken care of by putting a heating mat or stone in the vivarium (for warmth) and then placing a lid on the tank (to keep the heat in) but the lid is left slightly ajar so air can move through the tank (for ventilation). Hermit crabs are quite difficult to maintain if you don't "tick all the right boxes", and I'd encourage you to review their needs carefully. Once sick, there's little that can be done for them. Many books have been written about pet Hermits, but in the meantime, why not visit one of the several good web sites dedicated to their care. I happen to like this one: http://www.hermit-crabs.com/ Cheers, Neale>

Land Hermit Crabs and Softened Water? - 8/14/03 HI, <howdy> can I give my land hermit crabs water from my tap if we have a water conditioning system that uses salt? Kara <not recommended, my friend. The salt exchangers impart excess chloride that has been demonstrated to be a problem with some animals. Please do bypass the softener and/or keep a jug of spring water handy (not distilled... too pure). Kindly, Anthony>

Re: (land) hermit crab I'm not sure if land crabs are your area, but if so I would very much appreciate a reply. I have had a land hermit crab for over a year now. He's to all appearances happy and healthy, except he has lost quite a bit of color. In fact, the last time he molted he was just about translucent. He has a choice of many foods: Hikari "Crab cuisine", Tetra/Terrafauna "hermit crab cakes", Aquadyne mix of goldfish food and vegetables, and Hermit Haven hermit crab food. He has a large water dish with sponges, shells, and Cholla wood. He also gets salad or other veggies from my meals. His water is distilled, and I change the shells when it appears that the calcium has come off of them. Do you have any ideas as to what could be happening to my crab? Thank you very much for your time. ~Melissa <Hi Melissa, it sounds like you take excellent care of your hermit crab. Varied diet, good water, clean living, the only thing that I can think of that may be missing is sunlight. A full spectrum daylight fluorescent bulb may help him/her out. My experience with land hermits is limited, but it sounds like you are doing everything correctly, I would try adding some daylight.>

Land hermit crabs hi, I brought 10 little land hermit crabs back from Mexico for my son for Christmas. they are in a large Plexiglas tank with little stones and some awesome climbing sticks. I have hermit food and a sponge that I keep quite wet. I mist them daily and I have provided lots of shells. (they are changing them like crazy) two of them are connected right now and they are making "clicking noises" are they fighting? how do they mate? can you give me any advice? when I took them, I vowed to keep them alive and I want all the info I can get. thanks, Julie Swann <Hi Julie, I am not familiar with the actual mating ritual of the land hermit crab. I would be willing to bet they are fighting, most likely over a shell. While searching on google.com I stumbled upon the link below, it appears to have a lot of information on land hermits http://www4.tpg.com.au/users/vanessap/hermit/cs/cs_gender.html Hope this helps, Gage>

Painting hermit crab shells 1/4/05 My kids want to paint their Hermit's next shell. What kind of paint should we use? thanks <use non-toxic "baby-safe" acrylic paint like you'd find at Home Depot for painting children's furniture... or better still, perhaps find smaller portions and more colors at the craft/fabric stores. If it says "baby safe" then you are in business :) Anthony> GOT CRABS? We recently got a hermit crab from Texas and we do not know what it eats and where we should have it Tara Brooks < Go to ZooMed.com and get their new book on hermit crabs. They even have a couple of hermit crab kits with everything you need including a beginners book to get you started. In the meantime, hermit crabs are tropical and require a heating device to keep their terrarium between 78 and 83 degrees. The Zoomed ReptiTherm UTH works well as a heating device. They do require a relative humidity of 70%+, so a water dish with a sponge in it is really needed. For lighting the daylight blue and nighttime red bulbs really show them off. Hermit crabs are very active at night and the red bulb allows you to observe the crabs without really frightening them. The bottom of the terrarium should have some clean fine sand and a branch or two for them to crawl on. They do best on a commercial hermit crab food. The big problem with these crabs is that they dry out and need to be misted often. -Chuck>

Hermit Crab Substrate I could not find anything on your web site but I would like to ask you a question. Is used fish tank gravel OK to put in my hermit crab cage with half sand and half used fish tank gravel? < As long as the materials are well washed then there shouldn't be a problem.-Chuck>

Hermit Crabs I have a question about taking good care of my salt water hermit crabs. I have a picture of them to help you out. I got them in Florida about three weeks ago and they have done just fine, they have tried out new shells and got back in there old ones then back in the new ones. Right now I am feeding them dog food cut into little pieces. Can you also tell what to feed them? < There are commercial hermit crab foods available at pet shops that sell hermit crabs.> There water has been changed like every other day and is supplied with oxygen. There sand cleaned out too. I forgot to mention that I have three of them. They are not being kept in an aquarium because I don't have the money or room for that and it's not medal anywhere. The crabs are in saltwater and the water is almost room temperature. So tell me what else needs to be done in order for them to have a happy life and environment? < Don't let the humidity get too low or too cool. A cool dry environment is just the opposite of what they need and they will not last too long unless the are kept warm and humid.-Chuck>

Transporting a hermit crab 7/10/05 My 7 year old daughter who is currently in Wyoming visiting her dad has purchased a hermit crab. I am in Idaho and the plan was to drive to Rock Springs Wyoming to pick her up and then on to Bismark, North Dakota for a 3 day family reunion. At that point we would all return to Caldwell, Idaho where we live. Is it possible to transport this crab with us the entire way? <Yes, certainly> If so, what do I need to do to guarantee its safe and healthy arrival? <Keep it and its food, gravel in its container... along with a damp sponge (for moisture, humidity), and set all this down on the floor, level, in the shade. Bob Fenner> Never Too Young To Get Crabs! - 08/20/2005 I'm twelve years old and recently went to the beach. <Let me first open with a couple of statements.... I am TREMENDOUSLY impressed, and pleased, with your grasp of basic grammar and spelling. Let this be a lesson to all those older, more experienced folks out there - make proper sentences, use proper punctuation and capitalization. Nicole, we truly appreciate this! Thank you! (Hey Bob, I got the "truly" right!)> <<Heeeee! RMF>> I found a shop that sold land hermit crabs, (they seemed happy and well-treated) and they sold some really tiny carrying cages. The lids are plastic, with slits. Mine is probably one gallon, and I have two crabs. <This is quite a bit too small for land hermits.... though it will serve as an adequate temporary home, if you can keep the humidity very high.> They have purple claws, though I'm not sure what the type is. <Many possibilities. All have the same or similar care requirements, and all make excellent pets. You will enjoy caring for these guys, I'm sure!> They seem to get along well, I have: Sand made of calcium, completely edible Hermie Food Water dish, two inches deep but has stones below (No possible drowning, sand inside means they go in) Climbing surface Fake plant <I would strongly recommend that you look into a larger enclosure (10 gallon tank, if possible) with a lid that covers the tank quite well, to retain humidity. Another requirement, eventually, will be a container of saltwater - contrary to some literature, ALL land hermits available for sale in the US do, in fact, come from marine environments and do require saltwater in addition to freshwater. I'll give you some links to some good resources at the end of this message.> Okay. I don't have a spritzer, but I live in Austin and it's pretty humid, plus I bathe them every day. <I strongly urge you not to bathe them daily - or at all, for that fact. Once they're in a larger space, make one of their water pools deep enough that they can go completely underwater if they desire - they'll keep themselves clean. They do not have people bathing them daily in the wild.... This can actually cause them harm in the long run, mostly stress-related, I fear.> Do they definitely need a spritzer? <Unless you're dripping condensation off the end of your nose right now, you'll need to get that humidity up. Covering the lid with some plastic wrap (leave enough uncovered for air exchange) will help, and "misting" their container daily will help, as well.>> I also don't have a humidifier or thermometer, but our house is always on 78 or 80. <This temp. is fine.> And can you use a spritzer from a body spray if it is empty, soaked, and dishwashed? <I would not.... You can probably get a cheap spritzer in the plant section in your local discount store, or maybe even a grocer's or drugstore.> They are a big hot pink shelled one (Sebastian) and a small pale pink shelled one (Ariel). <Make sure to offer them more shells of varying sizes.> Sebastian is always willing to walk on my hands, and never pinches. He is especially active after bath. Ariel I can see walking but if I am loud she hides, and I cannot hold her, because she always retreats. She does flip over and walk around in bath, though. Anyway, they are always together, and seem to cooperate. But, today at about 9:30 tonight, they were away in their shells hiding (usual during the day) but one of Sebastian's left legs was lying on the sand. <Possible result of stress.... This may be no problem at all, as the leg will re-grow - but do please let him have some time to rest.> I removed it, and held him and he still seemed fine, although he was a little off balance. I bathed them and they were fine. <Again, this may be a major source of stress for them.... let them keep themselves clean, it is better for them.> Now, the two are together, not fighting, just away in their shells. What should I do? Sorry that I have so many questions! Oh, and tonight I'm going to separate them. Please respond as soon as possible! <Mostly, I would recommend, as above, try to get a larger enclosure for them, provide fresh and saltwater, get that humidity up (pronto! very important!), and let them chill out a bit to recover from the great ordeal of moving into a new (and obviously loving) home. Try the following for more information: http://www.hermitcrabassociation.com , and http://www.hermit-crabs.com . Wishing you, Sebastian, and Ariel well, -Sabrina>

Hermit Crab, Change of Clothes - Good Land Hermit Owner/Information! - 10/15/2005 Hi, <Hello.> I recently got a small hermit crab as a birthday present. Well, truth be told, his shell is really small, but Gerald himself is actually quite a bit bigger than his shell should be. <This is actually not uncommon with newly purchased hermits.... Hopefully in your care he will find something larger/more suitable.> So, after reading in several places that they need to switch shells, I've offered him a variety of new shells in different sizes, with different openings, painted, and natural. <Painted shells are extremely rarely accepted, unless there is nothing of the right shape/size otherwise. Just a heads-up.> From what I've read, hermit crabs seem to change shells whenever they come upon a new one, <Mm, not that often - not by a long shot.> but this little guy just wont leave the one he has. I'm a little worried, because I've read that if they don't change into a shell large enough it could be really harmful for them, and I'm not quite sure what I can do to help the situation. <A bit of information regarding this - there are a number of different species of hermit crabs.... all of genus Coenobita. Of those most commonly offered for sale in the US, a couple of them (C. compressus and C. rugosus) are a touch more hesitant to switch shells than others. C. compressus will hold out a very long time before changing shells, if there is nothing that they really like around. The only shells that my own C. compressus will use are Natica/"moon snail" shells.... some are called "shark's eye" or "whale's eye" shells. I would urge you to try to find out what species your hermit is, and if you believe him to be C. compressus, try to seek out these moon snail shells. C. rugosus will take moon snail shells sometimes, as well. Other hermits will usually take readily to Turbo snail shells.> Also, I was wondering if his present living situation is as it should be. He is in a 1.5-2 gallon plastic aquarium, <Mm, I would increase this to a 10-gallon tank, minimum.... especially if it is a C. compressus, which is a very active animal.> with Calci-sand, fake plants, dishes, <A comment here, regarding water/water dishes - contrary to what some might say, all hermits are at least *somewhat* marine in nature (some more so than others) and require saltwater in addition to freshwater. I would urge you to use a quality synthetic sea salt like Instant Ocean for making up saltwater.... you can store a container of it and use as necessary.> a sponge, and a coconut to hide under. I've been keeping the temperature between 70-75 degrees and humidity between 70-80%. I was wondering what % of humidity is too high, and what will happen if it does get high? <Actually, the humidity is fine where you've got it. If it gets too high occasionally, it should not be a major problem. Just don't let it drop below 70% for an extended period of time, lest he suffocate from his gills drying up.> Thanks! Kat <One last comment - hermit crabs are quite social animals. I really urge you to move up to a larger container and provide a couple of friends (preferably of the same species, but that's not terribly important). Also, as far as foods and feeding, be sure to include some foods high in iodine and calcium content - you can use a calcium supplement manufactured for reptiles to add to their food. Thawed frozen human-consumption shrimp tails with the shells still on are an excellent food high in iodine. Wishing you and your new pal well, -Sabrina>

Hermit terr. crabs FAQ... NNS 4/10/06 hi , i lives in Singapore and i have a few question that i cant find on the internet and sincerely hope you could help me with this i would like to know that could it due to my country temperature ( its about 20+ degree Celsius) that make my hermit crabs (species : Coenobita rugosus) inactive ? <Possibly, yes> when i buy them , i was given a tank with the sand lesser than 1cm in height , could it due to this that's why my hermit crab does not moult ? do i need to buy additional sand to add on to it? <Shouldn't be the sand depth. Likely nutrition, moisture/humidity> i wanted to put some of the dried leaves that i find along the road inside the fish thank but if the leavers is poisonous to human , would it kill my crab too ? <Too likely, yes. There are some "aquarium safe" terrestrial leaves one can use though> and erm i tried extremely hard but i couldn't find out the maximum size a Coenobita rugosus could grow up to , and to my knowledge , there are different type of shells in terms of their design , so will they switch home even if the shell design isn't what they use normally ? <Yes> lastly , i may emailed to the wrong address , sorry if i did =( but please reply if u can help me =) your sincerely, jimmy =) <Please see here re size: 67 g.: http://www.crabstreetjournal.info/species/Crugosus/index.html Bob Fenner>

My pet Hermit crab 1/10/07 Hi I am Lauren <Hi Lauren!> and I have recently taken in a saltwater hermit crab as my pet on holidays... <How is he only a pet on holidays? Is he in a reef tank, salt water tank... what?> we went on 2 different websites when we got home from our holiday which was a day after we took the hermit crab in it said to supply shells for them so we put in one which was not for the hermit crab to change in to but for it to get to land ..then the next day my dad told me he moved in to it but the problem is it is to big for it and he struggles to carry it.. now what should we do we wonder and hope you can tell us...Thank you <He will not move into anything he cannot handle. It may have a problem with mobility but will grow into it. No worries here. Jen S><<RMF suggests providing more shells... for this Hermits choosing>>

Freshwater hermit crabs 4/22/07 I can't seem to find much info on freshwater hermits. I know they do exist, but how would I go about finding some? Will they live in an African Cichlid tank? <All so-called "freshwater" hermit crabs are actually amphibious, and as such, unsuitable for use in an aquarium. The only truly non-marine, fully aquatic hermit crab in the trade I'm aware of is Clibanarius tricolor, the blue-leg hermit crab. It does very well in brackish water aquaria at SG 1.010+. It cannot be adapted to freshwater. Cheers, Neale.>

Hermit crab & Sand 7/25/07 Hi My name is CJ, I am 12 and have my first hermit crabs (3). Is it okay to use regular beach sand for them to crawl on or do I need a special type of sand? Also is it okay to have different types of hermit crabs living together. For example I have a large strawberry living with 2 regular pet store hermit crabs. I am not sure what type they are, but they are night bright red like my strawberry, more of brownish/grey color. Presently I have them living on aquarium gravel and marbles. Thanks, CJ <Hello CJ. When keeping hermit crabs, the optimal sand is calcium carbonate enriched sand, sold for crabs as well as reptiles. Crabs use the calcium carbonate as a dietary supplement for their skeleton. You can buy this stuff from any pet store. Some crab-keepers like to mix sand with coconut fibre ("coir") at a 50/50 ratio. The point to the coconut fibre is it stores moisture, which is essential for the hermit crabs. The crabs need the humidity in the air for their "lungs" to work properly, and when they feel the need, they will dig into the sand/fibre mixture to cool down or sleep. So, much happier crabs! Coconut fibre can be purchased in big blocks for a couple of dollars and after soaking in water you end up with gallons of the stuff. It doesn't change the pH of the substrate (unlike peat or soil) which is a major plus, and being so cheap you can easily change it every couple of months or whenever it starts to get dirty. Being nice and dark it also highlights the colours of the crabs, and you get a much more natural looking environment than just using plain sand or God forbid one of those hideous coloured gravels. Cheers, Neale>

Terrestrial Hermit Crab Habitat: How much weight in a terrarium? Sys. 11/8/07 Hey all, <Hello,> First to say, love the site, I keep up with it on a regular basis to make sure that my fish are well taken care of. You guys do a marvelous job! <Thanks.> Next, explaining a bit about my actual question, lol. I recently decided to get into terrestrial hermit crab keeping since I work in a biology lab at my college and they keep one or two little crabs... They're so fun and cute, I started looking into what it takes to keep some of my own. <Ah, yes, they are nice pets. Crustaceans generally make very entertaining pets but they do have specific needs. In the case of a hermit crab, it needs warmth from under the vivarium, a certain amount of humidity, water for bathing in, a varied (mostly plant-based) diet, and (often overlooked) the company of at least two other hermit crabs. The "bath" is one tricky aspect: different species need freshwater, brackish water or salt water baths. Make sure you identify the crabs on sale, and clear this aspect up before purchase. To be fair, the standard species is Coenobita clypeatus and that one is fine with freshwater; but oddball species are also sold, and may be particularly attractive because of their unusual colours and shapes.> For starters, I do have an empty terrarium, which is why I was looking for a new sort of pet to keep, it has ventilation holes with small screen covers, so there is no converting it to a fish tank of any sort, it was meant to be strictly a terrarium. (Originally it was bought to house some Jackson Chameleons, which was many, many years ago and they've hence passed on, unfortunately.) It's made by Oceanic and seems to have fairly thick glass, thicker than my ten gallon at least (roughly twice as much), from what I can tell from general observations. It's also fairly large, roughly three feet by two and another two and a half tall. <Sounds ideal.> Now, onto asking the question. I want to make sure the crabs would have plenty of digging/molting depth, so I was looking at how much sand I'd have to put into this thing... And a site was brilliant enough to bring up the point that some terrariums really aren't meant to handle heavy loads. So I was wondering if it was actually safe to put as much sand as I'd need into it and not risk the tank. Now there's a few things I was thinking of doing... For the record, this terrarium currently sits on a pretty sturdy metal frame work that it came with, but there is no underneath/middle support, it's strictly the frame work that it rests on (I'm not sure how crucial that is, so thought I'd mention it). <You actually don't need masses of sand, and in fact a mix of sand and coconut fibre (available in reptile shops) is the ideal. In the wild they burrow into leaf litter, and this mix replicates this perfectly. The coconut fibre holds moisture well, which is critical to hermit crab health in the long term. Anyway, the mix of fibre with a bit of sand for stability will add very little to the weight of the vivarium.> Now, I can take the tank off the current stand and sit it on the floor (it's tall enough that viewing is still fine like this), so that I don't have to worry much about the weight at all, but I have tile floors and I'm a little worried about the tile lowering the overall temperature of the tank. I could also buy some scrap carpet or material to sit it on so that it won't be directly on the cool tile, if that would make a difference. <The ideal here would be to place polystyrene tiles on the table, put the heating mat on that, and then the vivarium on top. The heating mat should have instructions about this. The loss of heat by conduction through the base of a vivarium is pretty trivial compared with, for example, warm air rising out the top of the tank.> I can also buy a piece of plywood or something and use it as a brace for the bottom of the tank, placing it between the framework and the bottom of the terrarium, but I'm not entirely sure what exactly to use or how well that would work. <Sounds overkill to me.> I could also leave the tank where it is and trust it's sturdy enough to handle the weight of the sand... I'm fairly certain a tank this size was meant to handle fairly heavy reptiles and it's possible I'm worrying over this for no reason whatsoever, but I thought, better safe than sorry, and I should ask some people that might know more about how much weight a terrarium could take. :) <Should be fine. Test it out before adding the animals, and if all seems well, press on!> Alright, think that was all I needed to pester you with. Thank you soooo much for your time and consideration! It's extremely appreciated. ~Caitie <Hope this helps, Neale>

Re: Terrestrial Hermit Crab Habitat: How much weight in a terrarium? 11/8/07 Thanks for the response, I'll pick up some coconut fiber substrate tomorrow to mix in with the sand. That should take some of the weight out of it, I think, not a lot, but still... I was just worried because I know they need a lot of burrowing room so that they'll molt properly, and I do intend to have some jumbos at some point, either from the littles I'll get growing up or just starting with some jumbos. Everything I've read thus far suggests having at least double the crab's height in sand. So yes, I was a little worried that much sand would be fairly heavy. <Mix the sand in with the coconut fibre, with the coconut fibre being 90% by volume. The sand is really there just for stability, though they may also use sand during moulting (crustaceans have structures called statocysts into which grains are sand are placed during moulting; these act as balance organs).> The only thing I have a further question on is the heating pad for underneath the terrarium, wouldn't that be just fine attached to the bottom of the tank, since I'll just leave the tank where it is on the metal framework? (i.e., there would be nothing underneath the heating pad, it would just stick to the exposed bottom.) <Sounds fine. But do check with the specific heater: all are different, and the manufacturer will state best practise for that particular model.> And do I really need an under tank heater if the overall temperature stays around 80? <If you live in Caribbean where these crabs come from, or somewhere else in the tropics, then no, you don't need a heater. But if you live in the continental United States or Europe, then yes, a heater is important. The danger with keeping tropical animals at room temperature is that we don't appreciate the variations across the year. Even in, say, California or Italy, the summertime temperatures might be fine, but in winter once the air temperature drops below 25 C//77 F the poor crabs become stressed. They are adapted to warm, humid conditions. Under tank heaters don't cost very much and cost very little to run. If your home is warm most of the year, then the heater will be off much of the time anyway. But it'll be there as a back-up for when it *does* get cold, producing warmth and humidity, and keeping your crab cozy and active. After all, these crabs are fun when they're scooting about climbing stuff and checking out shells. They are incredibly boring when they are cold, morose, lethargic or sick.> That way the top of the sand would be warm and the under sand would be cool, like in nature? (Least it is if I'm remembering my last trip to the beach correctly, lol.) <In the wild, the soil is actually a "buffer" used to escape extremes in temperature. When it gets too hot (e.g., at midday) these crabs will burrow into the cooler, moist sand. But at other times, for example during storms or cold snaps, the sand will be a relatively warm and dry place they can wait out the bad times. Your job is to provide something as close as possible to the tropics: warm humid air, substrate for digging into, water for bathing, and a glass lid over the tank to keep the humidity inside the vivarium.> Again, thanks for your input. :) <Good luck, Neale.>