One of my Fiddler Crabs molted Saturday night/Sunday morning. He also lost his big claw and 2 legs in the process. I was going to change the water and clean the tank Sunday morning and saw the molt laying in the tank. I left it as it was, and still is, and did nothing to the tank. My question is, how long do I leave it in there? I have read that you are supposed to leave it as they will eat it as it provides them with calcium.