A couple times, I purchased hermit crabs, the first time 1, the next time 2. They all died about a week or so later. I think it's because they wouldn't eat anything I gave them. I tried hermit crab food, and vegetables. One of them took a piece of corn and crawled off with it, but didn't eat it. I also kept their tank moist, and sprayed them regularly with dechlorinated water. I really want to get hermit crabs some day, and keep them alive. What am I missing?