Nerite snail hibernating?
I got a tiger nerite a few weeks ago (named Eddard, to go with my Game of Thrones themed tank), along with a piece of driftwood for him to eat. Eddard was very active, roaming all around the driftwood and keeping to himself, but three times in the past 24 hours I've caught him in the sand laying on his back with his trapdoor hanging open, basically asking to be attacked by the other fish in the tank. He doesn't smell, and when I close the trapdoor for him and tug it, he resists me, so he's clearly alive. The first two times I put him back on the driftwood, but at the moment I've put him shell up in the sand near the driftwood. Do you think he's sick, or just hibernating or in a food coma or something?