One of my snails broke his shell a while ago, and for ages it didn't grow back and he stopped eating. Then i put him in a tank on his own and he started eating again. His shell grew back, but the new bit was really thin and his body wasn't attached underneath the new bit. Now there is a huge crack down the middle of the new bit. He has a cuttlefish bone but i don't think he's been eating it. I was thinking of getting him liquid calcium - where could i get it? Does anyone know what else i could do? If anyone wants to see pictures of it i could email you.

Also i've been getting mites in the tank and i sometimes find them crawling on him. They don't seem to be harmful but i'm worried they might get inside him. Any help or advice would be much appreciated. Thanks.