Crabs keep dying

[Guest]

Hi,

We originally purchased 2 crabs, PP's I think. One went into molting within the first month and died during the molt. Lost his large claw and soon died.

We bought another crab so the first one would not be alone, he soon went into hiding and shortly after that (a couple of weeks) we found him hanging out of his shell dead.

So, we go and purchase a third one, he goes into molting about a month later and we leave him alone. All seems to go well and then he starts running around without his shell. The same day he goes back into it but by the next day we find him out of his shell dead.

We are really upset about this. We have a small aquarium with half sand and small gravel. We keep the humidity at 70% or so and the temp varies between 70 and 80 degrees. We keep a salt water dish and a fresh water dish (no chlorine) in the habitat. We can't seem to figure out why they keep dying? The forth one seems fine and still alive.

My 11 year old son is really depressed about this. We get them home and get acquainted with them and within a month or two they die even though we are doing everything we can to take really good care of them.

We live in Colorado so it's cold and dry but we put a heater under the tank . I have measured the temp of the sand and gravel and it's around 80 degrees.

Any help would be appreciated.

[EGcrabber]

What I can see is that you tat is a bit dry, it should always be above 75% and the temperture shouldn't go below 75. But just to make sure, can you please fill out this template?

1. Substrate used?

2. Humidity % level in crabitat?

3. Temperature of substrate in crabitat?

4. Temperature of crabitat?

5. Location of gauges?

6. What is your heat source?

7. Types of water available?

8. Dechlorinator used?

9. What do you feed?

10. How long have you had the crab in question?

11. Do you know the species?

12. Do you bath them, if so how often and with what?

13. What type of housing are they in? Tank? Plastic box?

14. What size is your tank?

15. How many crabs are in the tank? What size are they?

16. How deep is the substrate?

17. If you take your hermies out daily to exercise, do you mist their gill area first?

18. Has there been any cleaners, paints, perfumes, air fresheners, candles, or smoking near the crabitat?

19. How often do you clean/sterilize and how?

20. Any unusual odors?

21. Do you use sponges? Are they rinsed daily with dechlor water? Are they exchanged every 2 days for a sterile one?

22. Do you feed fresh food? When do you remove it?

23. Are your hands clean before handling?

24. Has there been anything new added to your crabitat recently?

[Tremors]

I'm sorry that you are having trouble with your crabs. Are the sand and gravel mixed together? Also, are you sure that the crabs were molting when they died?

It would also help us figure out what is wrong if you could fill out the help template that EGcrabber posted, so please do.

[Guest]

1. Substrate used? White Calcium carbinate, magnesium carbinate sand. I purchased the larger bags marked for reptiles. It's the same brand and content as the little bags marked for crabs. I also have some small gravel for fish tanks on the other side to give them two surfaces to be one.

2. Humidity % level in crabitat? Somewhere between 70 and 90%

3. Temperature of substrate in crabitat? 80 degrees

4. Temperature of crabitat? 75-78 degrees

5. Location of gauges? mid tank between the substrate and top

6. What is your heat source? Crab heater strip under tank. Tank is glass.

7. Types of water available? Salt and fresh

8. Dechlorinator used? None use bottled Spring Water

9. What do you feed? Crab pellets with a little water to soften

10. How long have you had the crab in question? from 1 to 3 months depending on which one died.

11. Do you know the species? Purple Pinchers

12. Do you bath them, if so how often and with what? No

13. What type of housing are they in? Tank? Plastic box? Glass fish tank w/glass lid that we keep with a small opening for air

14. What size is your tank? Small, 2.5 gallon not sure?

15. How many crabs are in the tank? 2 at a time What size are they? Small to medium. About the size of malted milk ball (only thing I could think of). That is their physical size not the size of their shells.

16. How deep is the substrate? 3-4"

17. If you take your hermies out daily to exercise, do you mist their gill area first? We don't remove them that much but do mist them when we do remove them.

18. Has there been any cleaners, paints, perfumes, air fresheners, candles, or smoking near the crabitat? No

19. How often do you clean/sterilize and how? Once a month?

20. Any unusual odors? At one point the tank was very humid (glass steamed up) and the sand was wet and we started to get a funky odor so we cleaned everything and dried up some water that was collecting under the sand.

21. Do you use sponges? Are they rinsed daily with dechlor water? Are they exchanged every 2 days for a sterile one? No. Only change when we clean the tank.

22. Do you feed fresh food? Every 1-3 days When do you remove it? Leave food in tank all the time.

23. Are your hands clean before handling? Mostly.

24. Has there been anything new added to your crabitat recently? No.

[Guest]

Yes. The last crab that died successfully molted his entire exoskeleton and seemed happy running around a couple weeks later. Then got out of his shell for several hours. Then got back in. Then out the next day and by the end of the day we found his little dead body

What can kill them quickly? How long without water can they go? With a lot of humidity the water does evaporate quickly. We fill two dishes in the morning and they can get pretty dry by the end of the day.

[starmaiden]

We fill two dishes in the morning and they can get pretty dry by the end of the day.

This sends up a red flag to me, as well as your hermie running naked, that perhaps your tank is hotter than you think! Crabs sometimes will go naked when they are too hot. And your water shouldn't be evaporating that fast unless your dishes are extremely small and shallow. What size is the UTH under the tank? Do you have a warm side and a cool side so they can be where they are most comfortable?

[Guest]

The heater is in the middle of the tank. I measured the substrate with a very accurate thermometer and it read 80 degrees. How hot is too hot? Everything that I read stated up to 80. When I did not have the heater underneath, it was on the side glass the crabs seemed too cold and did not move much, temp as around 68-70.

Also, the water dish is the one that came with the original habitat pretty shallow, like less than 1/4" or so. We added a lid from a plastic container that is about 1/2" deep with sponge.

[Guest]

DO NOT throw away crab if they look dead, sometimes they're molting.... keep it for couple days if they smells then throw it away..

The first death i threw away i dunno if he was really dead or.. molting.. it's really sad... death is still unknown... i feel like a murderer for not knowing if he was dead or not..

[EGcrabber]

I do not suggest you only feed your crabs commercial food. They should have a variety of fruit and vegetables, along with some foods that contain protein like eggs. They should also have a source of calcium, which is very important.

[Guest]

Crab was dead. laid out flat no movement of antenne, out of shell and had just molted exoskeleton. I find it hard to believe they can just lay there no movement at all looking dead. Can they? I touched him, no response.

[starmaiden]

he heater is in the middle of the tank. I measured the substrate with a very accurate thermometer and it ready 80 degrees. How hot is too hot? Everything that I read stated up to 80. When I did not have the heater underneath, it was on the side glass the crabs seemed too cold and did not move much, temp as around 68-70.

OK, that sounds fine, as long as they have a place that's cooler. My air temp in my tanks is about 78F, but my substrate temp is 80 by the UTH (I side mount) and 74 away.

Just curious, what type of salt water mix are you using?

Although I can't immediately see any reason why your crabs are dying, except for Post Purchase Stress, you might want to consider getting a larger tank for them and deeper water dishes so you don't have to refill as often and a larger tank is easier to stablize temp and humidity and provide both a warm and cool zone for them. 10 gallon tanks are really cheap, only about 12 bucks at Petco. And you can often find them for free at garage sales and in the classifieds.

Here's the topic on what Post Purchase Stress is:
Why did my crab die?

[starmaiden]

Crab was dead. laid out flat no movement of antenne, out of shell and had just molted exoskeleton. I find it hard to believe they can just lay there no movement at all looking dead. Can they? I touched him, no response.

Yep! But I doubt this was the case with your crab since it had just molted. I suspect he really had gone to that crabby beach in the sky. I usually leave them be for a day just to be sure. If I see no movement and they start to smell, then I know I can make funeral arrangements.

[Tremors]

Most commercial hermie food has bad preservatives in it, so I would recommend buying some of NaRnAR's food (she is a member here) that she sells on Ebay. Her store is called The Happy Hermit and there is a link to it in the drop-down box labelled Shopping that's on the right. If you don't want to buy any more food for them, you should at least try to mainly feed them fresh foods like fruits, vegetables, meat without any kinds of seasonings or salt, etc. Nothing with preservatives or wierd ingredients though.

Also, a 2.5 gallon tank isn't big enough to keep crabs in, so as soon as you can you should try to get a 10-gallon tank or larger. 10-gallons aren't usually too expensive.

Edit: Looks like I was writing this post while everyone else was posting.

[Ryanstein]

Yeah, what is your salt mixture formula? The boxes have a formula for how much salt per a certain amount of water, but my hydrometer, or salt mesuring do-hicky (it's actually a refractometer) mesures below salt water level sometimes, perhaps because I'm mixing very small batches of it. This isn't a problem really with the salt (I use IO), but rather with the mixture. You might want to check this out. Some sea salts for hermit crabs have a very low salinity, and this could be a problem.

[Willow]

The water dishes are too shallow. They should be about an inch deep, more if your crabs are large (of course, they should be able to climb out of the dishes easily so they don't drown). They should be able to get into the dish to fill their shells with water. They can die of dehydration if they can't fill their shells.