HCA: Hermit Crab Association

Hi All, I am a new crab mom, I have a 55 gallon tank that I house 7 crabs in. I have 3 small, 1 medium and 3 jumbos. 4 of the 7 went down under the night I got them on January 12,2019. 1 Jumbo went down and I have not seen him since. This is the thing, the Jumbo went down and after 3 months his shell submerged, I left him alone and in the next few days the shell looked like it was going back under... the next day his empty shell was upside down in the same spot it submerged? Since then the exact same thing happened with a small one. What could be happening??? I did find pieces of the jumbos exo skeleton, Well I think, it was just the shell with no meat in them. I still have not seen that jumbo since the first night and no sign of the little one...Any information would be much appreciated!

You might want to check all the shells to see if they are in any of them and count them to see if any are missing. I am a beginner crab keeper and none of mine have molted yet so you might want to consider your options.

Thank you , I have checked all the empty shells and they are not occupied and none are missing.... I feel so unsure ... thanks for your input

Hermits must stay shelled at all times. If you found an empty shell, then one needs to missing from elsewhere in the tank. If there isn't, I'm sad to say one of your crabs has passed, and you may not be seeing shed exo. Passing during the first molt is not uncommon and is known as Post Purchase Syndrome. It really sucks.

If you'd like, use the template in the ER section and answer those questions, and we can look over everything and see if something might be causing problems.

Sometimes crabs hide really deep in the shells. Smell the tank and different areas of the tank for a rotting fish smell. Also make sure that it was just the exoskeleton, and if I were you I would look deep in all the shells one more time. I hope it goes well!

Thank you all.. I know that I have done my reasurch and done my best... the shells are absolutely empty but I don’t smell the fish smell..., it will be what it will be

jumbos can molt for up to 5 months. good luck.