one of my hermit crabs died

Question
QUESTION: today i was changing out the water and food to give fresh and noticed that the bigger of the two wasn't going in and out of his shell like he does when he wants to play. yes the love to play with my hand!!! lol so i lifted him from his hole to see what was wrong and he was cold and then he kinda fell apart. the coldness didn't come from not having heat they are set at a perfect 81/82 24/7. as i was cleaning the sand where he past i noticed a spider in there. could or would a spider kill him? i am very broken hearted bout losing one of my buddies and really would be heart tearing to lose the other can you tell me some of your ideas please. at least i can try to protect my other one

ANSWER: Are you 100% sure that he was not molting? Was his entire body present including his abdomen? Do you still have his old shell?

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QUESTION: still have his shell haven't buried him do to rain and strong storms. he was in his shell when i picked him up. and he fell apart. ok i went and looked and he is gone. can't be far will let you know when i find him. i am so stupid. at least i didn't burry him. 2 hours later....... i found him he don't look the same was in some clothing. lol eating now thats my boy. he is always hungry. thank you

Answer
Don't feel stupid, it is an extremely common problem. If you have disposed of his exoskeleton he will need lots of calcium and protein. The best thing you can do is buy a peel and eat shrimp and offer it to him chopped up and steamed skin and all. The shrimp exo has a lot of the nutrients that he would have consumed by eating his own exoskeleton.

Calcium can be offered in the form of a cuttlebone (in the bird section), egg shells, corral, calcium powder, and others.