What I did was take a plastic coffee canister, the kind that most coffee comes in now with the built in handle, cut a hole (which took a little effort) big enough for them to feed out of near the bottom of the canister and mounted it in the coop with screws about 6 inches off the floor. Put the oyster shell in it, put the lid on it and had an easy way to keep it up off the ground, and it's super easy to pop the lid off and put more in. Weird tho, they don't get on top of it, which I'm happy about. Also, very easy to replace. After mounting it I thought I should have put washers in to prevent it from ripping through, but so far it is fine and has been in there for a few months.