I lost both of my mystery snails over thanksgiving break. The pond snail is fine though. No ammonia or nitrites in the water. Phosphates and nitrates very low. No salt since I got the snails. No chemical treatments currently. Oxygen level was fine, though the water did increase to about 80F over the time I was gone. Goldfish enjoyed the sauna, went into breeding season. Snails, not so much. I hate paying money for the darn things if all they do is keel over. I've got an add for pond snails on craigslist but no answers to it yet.