when I bought my first 4 snails, they were in a bare tank--no plants, food, algae, zip! Most were closed up. I was told that they mostly came out at night and ate and stayed closed up all day. I asked what kind they were and was told, some kind of mystery snail I guess. All the same. So I just picked 4 colors--yellow, gray, black and white.
Well, the "black" one was dead when I bought him, not sleeping. Looked all over my living room trying to find out what that terrible smell was

. The yellow one was a cana, that's why she ate my plants and got so big, the white one's shell just dissolved away and the fish picked it off and ate it. By then I'd found this site and got a clue about what was happening. Luckily for him, Dorian Gray--actually a blue snail but looked gray--had a much better life and lived for over a year. Fathered some pretty babies too! Thank you applesnail!!!