Well, I have 3 snails which I guess are mystery snails. They were very active, alwyes eating and moving around. Then I dosed my tank with melafix and primafix. Since then they became very lethargic sometimes just floating there hanging to a detatched stem of my plants. They r not dead. One time, I put one of them in a plastic conatainer with my tank water just to see it closely and there was this fluffy cottony stuff hanfing from it for a while. Snail experts....any suggestions?