I found Bruce today while cleaning the tank out. I hadn't seen him for weeks. He apparently died during a molt. He was the smallest crab I have ever had, about dime sized. Plus I bought him at the mall and they have a large death rate. After buying 3 more today at PetSmart (the conditions have improved greatly at my store, they even had a variety of food in the tank), that takes me to 14 crabbies.