Sad face, this makes me think of my poor attempt at having hermits. I was a teenager and bought one from a little kiosk thing at the mall around Christmas. I'm sure it was sickly and malnourished when I got it, but it lived in a small plastc aquarium thing (probably less than 1 gal thinking of it) I just fed it "hermit crab food" from a bottle, didn't have a humidity setup...He was gone by March
Looking back on it, it makes me wish there were more laws against that sort of thing. The kiosk owner didn't care about the crabs, I just went off of the pamphlet he gave me, and the crab (plus dozens of others) suffered.