HCA: Hermit Crab Association

I am a new Crab mom of 2 months, I did my homework before getting my hermits , set up the tank and adopted 7 crabs in a 55 gal tank, 3 smalls 1 medium and 3 jumbo’s. I got them 01/12/19. That night 4 of them ( 3 small and 1 jumbo) buried themselves .kniwign not to disrupt them I let them be... 19 days later the 3 smalls submerged and after 3 days 2 of them disappear again and I have not seen them since... at 5” days the Jumbo’s shell submerged and began to appear digging back down .... knowing that they know what they are doing , I let it be.... 57 days later his empty shell was flipped upside down at the substraight surface and no sight of the crab. Concerned I gently dug where the shell was seen, I found several claw and leg shells that were empty and no sign of anything else ??? Did they eat him???? Where did the two little ones go? Now 2 more jumbo crabs have gone down, I am sure to molt and all I have above ground is one small and one medium?? They hardly eat and never seem to go into the fresh water or salt water pools?? Does anyone have suggestions or ideas as to what I should do/ what happened? Distraught mew Crab mom!!!

That was 53 days not 5”

How deep is your substrate? Sometimes even if all conditions are perfect they can succumb to the stress they have gone through. If they're alive they're eating and drinking.

When you found the legs under the shell, was it a full leg or the exoskeleton of the leg?

How do I tell if it was an exoskeleton? the things I found were the shells with no soft body parts inside

If they are hollow with no body parts inside, it is exoskeleton. If there are crabs who are under the substrate, do not dig. If the crab did pass away, there's nothing you can do. If you dig, you could harm others who are under there and are alive. It is important to have enough substrate (3x as deep as your largest crab, or at least 6 inches, whichever is deeper), so they have enough room.

The only way I knew that my crabs were eating and drinking when I first got them, is that they were alive LOL. Just keep giving proper safe foods, and both dechlor fresh and dechlor mixed salt water made with marine salt.

Thank you so much, I have provided them with sea salt and fresh water and a variety of foods, just hope they are ok..

Do you mean marine salt? What brand of dechlorinator and salt do you use?

I use Instant Ocean Marine sea salt and Poland spring water. I give them fresh food, in a variety every day. The sub straight is 8” deal and I did have 2 under the tank heating mats, but when I read here they are no good I removed them and put on the back of the tank glass. I have right now 1 small crab and 1 medium crab still on top of the soil.... the medium named “Churchill” was my most outgoing and active crab, now he stays on top of a plastic cave in there and I do not see him eat or drink unless I put it up there for him ... he is not injured, that I can see?? Idk ... thank you so much for any and all help! Thanks for taking the time ...