New Owner trying keep crabs alive

[Flandry]

Hi everyone,

Great forum! I'm not sure if this is the right place to post this as I'm not sure if I have a situation requiring immediate attention. But I figured it wouldn't hurt to err on the side of caution.

Last weekend I was vacationing with my family at the Gulf Coast. For years, every time we’ve gone to the beach, my son has wanted a hermit crab. Not wanting a living creature to die from ignorance or inattention, and believing such a pet would be extremely challenging to keep alive, I’ve said no. But my son has matured, proven his desire isn’t a passing fancy, and we’ve had some experience keeping fish. He also finished his school year strong and we wanted to reward him.

So when we went into a souvenir store and he immediately went to the crab display, I felt he earned the right, though I’d still intended to say no. However, I saw that all the crabs in the display appeared to be the same type and that all were in the same ugly, obviously natural shells. In addition, something just look “right” about them. So, to my surprise, I said yes.

We bought two and from that moment we’ve been reading, buying stuff to support them, and reading more. At this point, we’re not sure where we stand on things. So I humbly ask for your feedback and advice. Per your directions, below is the completed template:

• 1. What kind of substrate is used in your tank and how deep is it?
  
  • Play sand and Eco Earth mix moistened with distilled water (eyeballed somewhere between 5:1 and 3:1 mix). Depth varies from 3” to 5.5”. The sand hasn’t settled and is fairly fluffy.
  2. Do you have gauges in the tank to measure temperature and humidity? If so, where are they located and what temperature and humidity do they usually read?
  
  • Yes. Gauges currently located a near the middle of the tank in section about 1.5” above the substrate (which is about 5” deep). Current temperature is 72° F. Humidity is 64%. Due to heater position, temperature varies across tank.
  3. Is a heat source used in the tank? If so, what?
  
  • Zoo Med Large 24-watt heat pad located on back, right side near top of tank. Gap of about 2” below heater. Substrate sloped so it does not overlap heater.
  4. What types of water are available (fresh or salt) and how is the water treated (what brands of dechlorinator or salt mix and what ratio is used to mix it)?
  
  • Two 1.5” deep Tupperware containers filled with water treated with Top Fin Tap Water Dechlorinator and left to sit 24 hours before first use. One container is freshwater, the other is saltwater made using Instant Ocean Sea Salt in a 1:32 ratio.
  5. What kinds of food do you feed and how often is it replaced?
  
  • Day 1 & 2: Souvenir store hermit crab food and distilled water.
    Day 3: Apple and distilled water. Both crabs ate this in good amounts. Good amount of poop found next day.
    Day 4: Carrots, Raisons, Peanut Butter (not sure if eaten) and dechlorinated tap water
    Day 5: Fresh Beef, Dried Mealworms (don’t think was eaten) and dechlorinated tap water
    Day 6: Dried Mealworms, Honey, Raisons (not eaten) and dechlorinated tap water
  6. How long have you had the crab and what species is it, if known?
  
  • Six days. Bought two Purple Pinchers in Cittarium Pica shells. All crabs at this store were in Cittarium Pica shells (none painted).
  7. Has your crab molted, and how long ago did it happen?
  
  • New. So unknown.
  • 8. What type of housing are the crabs kept in, what size is it and what kind of lid is on the housing?
  • Days 1-3: Large souvenir store box with not quite enough decorative gravel to line the bottom
    Day 4: Intended permanent home is a 20 gallon long All Things Living Reptile tank with locking metal grill cover. Substrate was 2” of play sand topped with one inch of Eco Earth. Tank was misted twice with distilled water.
    Day 5-6: Same as Day 4 except substrate is now 3-5.5" of moistened play sand and Eco Earth.
  9. How many crabs are in the tank and about how large are they?
  
  • One crab with shell is a little larger than a pingpong ball in diameter. The other is a bigger, but still smaller than a tennis ball in diameter.
  10. How many extra shells are usually kept in the tank, if any?
  
  • None currently. Bought five of the most natural looking shells that had openings slightly larger than one or the other crab. Still have yet to learn how to prepare them for the crabs.
  11. Have there been any fumes or chemicals near the crabitat recently?
  
  • No.
  12. How often do you clean the tank and how?
  
  • Have not cleaned yet. Bought a scooper that lets most sand/Eco Earth fall through.
  13. Are sponges used in the water dish? If so, how are they cleaned?
  
  • Yes. Bought one small sponge from the souvenir store (roughly 1x2.5” cylinder)
  14. Has anything new been added to your crabitat recently?
  
  • Complete setup is new. Other items: one small piece of Cholla wood, one resin cave/steps/ledge ornament, two small resin food dishes.
  15. Is there any other information you would like to share that might be helpful (anything that is regularly part of your crab care, playtime, bathing, etc.)?
  
  • We’ve misted tank twice daily on days 4 and 5.
    
    The crabs were reasonably active until Day 5 when placed back in their tank with the improved substrate. At this point, the smaller crab moved about 6” to the cave. The larger crab made two rounds of the edges of the tank, then a few hours later moved under the cave to huddle next to the smaller one. The cave is on the left back - away from the heater on the right back. Both crabs dug out about ½” of substrate beneath them and didn’t move at all the whole day. Today the two crabs have traded places. The smaller crab remains in a depression on the surface. The larger crab next to it has dug in where only the top of its shell is visible. Neither appear to have eaten or visited the water dishes.
  16. Please describe the emergency situation in detail.
  
  • Being completely new to hermit crabs, we’ve been working against the clock to learn all we can to give them the best chance of survival and, hopefully, long lives. Having done a lot of reading/lurking on this site, I feel there are many things that are still not right (temperature, humidity, substrate moisture, etc.). But having read about destressing/PPS, we’re now at a point where we don’t know how the crabs are doing and if we should attempt to due anything further at this point. For example, should any environmental conditions be changed immediately? I’ve read some advice saying the substrate should not be deep enough that the crabs can bury themselves from sight, so should substrate be removed? Is everything fine and should the crabs be left alone to destress? Etc.

Thank you for taking the time to read all this and lend us your expertise!

[hermitcrab101]

Besides meeting all your crab's crabitat, food and water requirements there's not much else you can do to delay or avoid PPS, although it is recommended to not handle your crabs for around a week to allow them to settle down and not stress them out. A couple notes on your set up, I would increase the tempature and humidity. You can do this by covering the crabitat lid in Saran Wrap and tinfoil (placement depends on where your heat lamp is) to increase humidity and as for tempature, replace the bulb with a higher wattage one. As for substrate, it should be 6 inches at the shallowest for small crabs. Deep and plentiful substrate is especially important for new crabs because crabs distress by digging, without substrate to destress in its possible for the crabs to die because they're stressed out too much.

[Flandry]

Thank you for the response! I'd read about covering the lid and we have plans to do that. But I wasn't sure if I should try to increase the humidity now, or wait a week. I've also thought about buying another UTH to help get the temperature higher. But again, didn't want to do to much too soon and hurt the little guys. I still have half a bag of Eco Earth and bought another 20lb. bag of play sand. But with the crabs settling into one spot and digging down a bit, I wasn't sure if now was a good time to be messing in the tank. Should I go ahead and do these things now?

[DragonsFly]

It is a very steep learning curve, but the good news is that you have in fact found the best place for information about how to keep these animals alive in captivity.

Unless the crabs are really quite small, you likely need deeper substrate. Wherever you read that substrate should NOT be deep enough to bury themselves was absolutely dead wrong. Crabs need deep substrate to molt properly (their entire life cycles depend upon this; denying them deep substrate pretty much guarantees they won't survive more than a few months, if that).

Temp for PP's should be between 75 and 85 degrees Fahrenheit (their comfort zone), humidity between 75 and 85 % . Because they breathe with modified gills, they must have high humidity or will slowly suffocate. Temps under 75 are problematic; temps under 70 are eventually unsurvivable. These conditions need attention immediately. Covering your lid will help. Cruise this site for more ideas.

I'm not sure, but it seems like you feel that the food has to be wet down? It doesn't; they are scavengers and you can give them food that is fresh or dried, without mixing it with water. It helps keep the tank cleaner if you give it to them in tiny, tiny bits (they are less likely to drag it around that way); otherwise, you can just give them food "as is."

People usually boil the shells (in half-strength MSW is a good choice) for a while before putting them in the tank, to kill any germs that might be on them. Otherwise, there's no other special "preparation" you have to do. It's a good idea to check out (if you have not already) the types of shells that PP's will actually wear and prefer ("Shells" Forum here), and note that it is not the overall size of the shell that is what is important in terms of "size" for the crabs, but the size of the OPENING (which is not directly correlated to overall size of shell).

I'm not sure how old your son is, but just a heads-up: crabs really don't make good "pets" for kids, in general. They are nocturnal; they regularly spend days/weeks/eventually months underground during which time they must not be disturbed but good conditions must be maintained; they are wild animals, so handling them is stressful to them, plus (unless your house is kept quite warm and humid) it is harmful for them to be taken out of their tank. The typical pattern is that the kids think they are cool and get the "I-wants," but (if the crabs are lucky enough that the kid has a caring parent), the parent ends up doing everything required to keep them alive while the kid loses interest. But you were not to know that.

Well done for caring enough to try to find out how to actually keep them alive; well done for only getting two; best wishes for the next few days or weeks during which time, no matter what you do, they still may succumb to PPS ("post-purchase syndrome," from the horrific traumas they have undergone in being "wild-harvested" and abused into captivity). Hang in there, and thanks again for caring!

[DragonsFly]

Thank you for the response! I'd read about covering the lid and we have plans to do that. But I wasn't sure if I should try to increase the humidity now, or wait a week. I've also thought about buying another UTH to help get the temperature higher. But again, didn't want to do to much too soon and hurt the little guys. I still have half a bag of Eco Earth and bought another 20lb. bag of play sand. But with the crabs settling into one spot and digging down a bit, I wasn't sure if now was a good time to be messing in the tank. Should I go ahead and do these things now?

Humidity and temperature are critical for life. In particular, without high enough humidity, they cannot breathe properly, so they are literally slowly suffocating. Covering the lid will help keep humidity in, and also will likely help the temperature increase somewhat.

Also, if your substrate was only recently moistened, and you did this with cold water, it will take a while for the substrate to warm up--once it does, it will help you maintain warmer temperatures. So if you just keep the warmth from escaping (and your surrounding air temp in your house is not too cold), you may actually not need to increase the amount of heat going into the tank very much.

Oh--also, I highly recommend putting your temp and humidity gauges on popsicle sticks or something similar, so you can put them here and there throughout the tank and get a better read on the temps where the crabs actually are. Sticking them to the side of the tank gives readings that are not as accurate, and also makes it more difficult to rearrange things. I also highly recommend having more than one of each gauge, because these factors are so critical for the crabs' survival. You should calibrate the humidity gauges, and--again, because it is so critical to survival--I never trust just one single gauge, even in a very small tank. Over time, they become inaccurate, so if you don't have another one in there to give you a clue that something may be going kaflooey with one of them, you could end up with problematic humidity for a while without knowing it.

EDIT: Oh, and yes, I would also increase the depth of substrate, if there is not at least about three times the height of your biggest crab. The first thing they may need to do is dig down and molt, so if the substrate is not deep enough (or not properly moist--"sand-castle" consistency), they can't do that and won't be able to repair any damage from being abused into captivity.

[Flandry]

Thanks for the responses!

Also, if your substrate was only recently moistened, and you did this with cold water...

Yes. I'm afraid we did do that. Tonight, before misting the tank, I warmed the water up.

I highly recommend putting your temp and humidity gauges on popsicle sticks or something similar...

That's genius. Definitely will do that.

Sticking them to the side of the tank gives readings that are not as accurate, and also makes it more difficult to rearrange things. I also highly recommend having more than one of each gauge

I've actually been moving the gauge around to measure things, but was leaving it on the lid. I've placed it on the substrate now. I also stuck a spare fish thermometer in the substrate until I can get another set of gauges (any recommendations?(

It is a very steep learning curve, but the good news is that you have in fact found the best place for information about how to keep these animals alive in captivity.

So true! I knew nothing about crabs last Saturday. This place has been an invaluable resource.

Unless the crabs are really quite small, you likely need deeper substrate.

They're pretty big. I plan to add to the substrate tomorrow. We can get it to about six inches in most places (it's about 5.5" where the crabs are camping). I'm uncertain about going higher due to the limited height of the tank (12").

Temp for PP's should be between 75 and 85 degrees Fahrenheit (their comfort zone), humidity between 75 and 85 %.

With all of you recommending getting to ideal conditions as soon as possible, we've added a thick plastic sheet to the top of the tank and misted the tank with warm water. Temperature is now at 74 degrees and humidity is 86%. The dramatic increase from not enough to too much humidity is concerning me. I hope we didn't overdo it. The crabs still haven't moved or dug any further down. Since we know they've eaten apples, we put some back in the tank tonight.

People usually boil the shells (in half-strength MSW is a good choice) for a while

Good to know. I assume MSW is marine saltwater.

I'm not sure how old your son is, but just a heads-up: crabs really don't make good "pets" for kids, in general.

Though I was no expert, I told him that for for several years. He remained steadfast in his interest. My son does have a different perspective on many things and I think he may actually be better suited to owning such creatures than many kids. I do hope he'll grow as a person as he cares for them. That said, I also knew I was signing up for the mission too when I said "yes" and am dedicated to providing any and all care as needed.

Well done for caring enough...

Thank you. That's praise that we can only hope to earn.

[mool]

Hello and welcome to the forum!

The advice you've been given is spot on! I wanted to address one thing not mentioned by anyone else and that is your tank. Reptile terrariums are not meant to hold the amount of weight that is necessary to properly house hermit crabs. The glass is usually very thin and the seal is not that sturdy. Aquariums meant to hold fish are better options because they are meant to hold water, substrate and aquarium décor without bursting or leaking.

Also, if your two crabs are fairly good sized you might already be in too small of a tank. I keep my two large/extra large crabs in a 55 gallon tank (soon to be too small); my 3 medium sized crabs in a 40 gallon tank and my 4 micro crabs (shell fits on a dime) in a 20 long tank.

You might want to plan for an upgrade in the near future. Petco usually has $1.00/gallon sales a couple of times a year. The next one will probably be in Nov/Dec. Other places to look are Craigslist, 2nd hand stores, and fish stores. Used and/or leaker tanks are fine; just no cracks in the glass.

I use and prefer glass lids, but other people use and prefer metal mesh lids that are partially covered in some fashion. Either is viable and has advantages/disadvantages.

Sorry to be the bearer of bad news on this one, but I'd hate to see your tank burst just when you get rolling.

Keep up the good work!!

[soilentgringa]

If you have an Exoterra you can use it for hermits. We have had members throughout the years use them and love that they can open them from the front.

This is the link to the HCA tank size guide.

http://www.hermitcrabassociation.com/ph ... p?t=108854

[mool]

Theirs is an "20 gallon long All Things Living Reptile tank with locking metal grill cover." Hopefully someone can chime in and say whether or not this tank is sufficient for their crabs.

[soilentgringa]

Theirs is an "20 gallon long All Things Living Reptile tank with locking metal grill cover." Hopefully someone can chime in and say whether or not this tank is sufficient for their crabs.

I think that it is fine. It doesn't need to be water tight for crabs, and a 20 gallon isn't going to have a super heavy amount of substrate anyway. As long as it is on a solid stand or table, there should be no issues. As far as the cover goes, wrapping it in plastic or securing some plexiglass under or over it will be good for holding in humidity.

[Flandry]

Yes. It's a 20 gallon long PetSmart brand reptile tank. We'd planned to add more substrate to get everything up to around six inches today. But we held off due to the concern the tank might not support it. The tank is on a metal stand. I've cut a piece of 3/4" wood and the tank now sits on top of it. Since we just bought it, I'd like to continue with this tank for a while if possible. That said, there actually is someone in my area selling a used Exo Terra Medium/Tall tank. I don't know if that would be large enough to consider and am having difficulty finding out how much substrate the tank can hold. Unless it's critical, I'm not going to disturb the crabs to find out how big they are right now. But rough guessing based on the HCA guide, I'd say one is large and the other is medium.

I had actually read about how awesome Ultratherm heat pads were before I bought the Zoo Med I'm using. I would have gone for one of those if I'd been able to get one locally so the crabs weren't having to wait weeks to get warm.

• Current Conditions:
  With the plastic sheet covering the majority of the mesh (a clear roll material that would work as a heavy-duty tablecloth), the humidity is much improved. Due to the high humidity, the tank was not misted today. But the humidity where the crabs are camped is now reading 80%, so we'll probably be misting again in the morning. The temperature where they are is about 73 degrees. It reads 78 degrees directly in front of the UTH. A thermometer stuck an inch into the substrate farthest from the UTH reads 71 degrees. There's enough room on the back of the tank to add another small-size UTH pad if that would be beneficial.
  
  The crabs remain exactly where they've been (in 1/2" pits on the surface), though I've seen small movements in both. At the moment, neither are fully retracted in their shells. What I have not seen is any movement toward the food or water dishes in about three days. I've read they can go without for up to two weeks. But we'll be relieved when they make an effort to tank up again. We continue to put fresh food out for them each night. We also saw a little bit of poop by one of the crabs this morning. This evening we bought some organic eggs and plan to see whether a bit of egg or eggshell will interest them tomorrow.

I want to thank you all again for sharing your expertise. I know when you become an expert and a regular member on a forum you end up answering the same basic things over and over again, and I appreciate your patience with me as I continue to read, observe, study, and build my knowledge of these fascinating creatures.

[soilentgringa]

No one here is an expert, so don't feel badly! We all started out somewhere.

Your tank is fine for right now, until your crabs grow larger.

Read the care guides and the files on molting. Crabs will bury for weeks to months without coming back up for food or water and it is imperative that they not be disturbed during this time.

[mool]

Like DragonFly said, the learning curve is steep. You are doing a great job of catching up.

As I am learning, the learning curve is also flexible. When I first stumbled across a crab in a free tank I got from Cragislist, I joined a forum to learn all I could. That was 8 years ago. I got all of the info I needed and abandoned the forum. I thought it was one of the two that formed this forum, but maybe not.

Anyway, I learned some things back then that at the time were thought to be true, but it's not necessarily so. Crab keeping is an evolving field and as more people do it; a larger body of information is available to share. Some of the information thought to be true 8 years ago has been proven not valid.

One of these is my advice about using non-aquarium containers. This was considered very risky and a huge no-no back then. I guess now terrariums are either made stronger or people used them anyway and nothing happened.

Another big one for me is not putting plastic of any kind into crabitats. This was a huge no no 8 years ago because plastic was toxic and it out gassed. I'm still not on the new bandwagon that plastic is okay. I see that most people use plastic decor and plastic water pools, but I'm not down with it (yet). I don't even like that the tanks are encased in plastic and have plastic strips on the lids. The only plastic inside my tank is the gauges.

Metal is still a no no, but as I peruse the pictures in the photo gallery, I see metal in tanks fairly often. Maybe that thought will change too, or those keepers will have un-natural die offs. Time will tell either way.

My apologies for scaring you about the tank being inadequate. Apparently it's old information that I retained and have to un-learn! I wish I'd of known this about a week ago because I passed on a free 75 gallon reptile tank with lids, heaters and lighting. It was in perfect, used condition but was not an aquarium. Live and learn...

[Flandry]

I'm glad to hear the tank should work, though I now see the significant difference in wall thickness between an aquarium tank and a reptile tank. When we add the rest of the substrate, there'll be about 30 lbs. in the tank. So I have to admit I'm a little nervous.

To my great surprise, the humidity is still reading 80%. However, the temperature where the crabs are has dropped from 73 to 71 degrees. The temperature in the house has remained constant. This is the exact opposite of what I was expecting to happen. Any ideas why this would happen? Would adding another small (8 watt) UTH to the back of the tank help?

Also, this morning we discovered the largest crab had gone underground during the night. No hole was left on the surface. Is this okay?

[mool]

I'm not sure what's going on with the temperature. I do know that it is perfectly okay to run multiple heaters on one tank. I do it on my 55 gallon; I run two 24w heaters on it. Currently, I have one unplugged because the tank has been closer to 88 degrees with both plugged in. I need both in the cooler months.

Edited to add: I forgot to comment on your buried crab. They often back fill their holes and tunnels, so it's nothing to worry about.