To big for it's shell

If your crab seems to be "falling" out of its shell, there is a very simple cure for that one. All you need is to go to your local pet store, [make sure it sells hermit crabs] and pick out a new good sized shell for your little guy. Also, make sure that it's going to fit. If it is to big, your crab will not like it. If it is to small, you are just running into the same problem as before. Pick out one that is not painted, with no holes. Most likely your crab will go over to inspect the shell when you bring it home. If your crab likes it, it will happily move into it! If it does not, it will go look for another different shell around it's tank.