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.

I stopped using cuttlefish for my snails ages ago when I learnt that the salt content is too high in cuttlefish bone. I was advised to use eggshells (rinsed first) and my snails love eating those! So I'd recommend you throw away the cuttlefish and use eggshells for the calsium instead. I put in fresh eggshells every few days.
As for the mites... they are probably coming in on the soil in the tank? So I suggest you give it a good clean out ...I certainly wouldn't want mites on my snails.

Ok i'll try egg shells. I've tried cleaning out the tank before and the mites just keep coming back whatever i do.

If it doesn't eat the egg shell, as mine don't, here's what I do.

I peel all the membrane of the inside of the shell and was it. Then I crush it using a pistil and mortar, add oats and sunflower seeds and crush these. This is an excellent nutrients boost and goals down really well with mine! Add a couple of teaspoons to its food bowl or a jam jar lid and add a tine bit of water. Stir it and until it's a think paste. It's easy to eat and very nutritious!

I think they've been eating the egg shells a little bit but i'll try that. Thanks

I've tried giving mine different types of eggshells; they like the most expensive ones the best. Columbian Blacktail seems their favourite but they will eat others (organic and free range).