One day, newt looked fine. Next day, it's swollen to twice its normal size. Skin looks a little rough but not discolored. Not eating. Usual low level of activity. Other newt is fine. I have some small snails in the tank, came with underwater plants, I guess. Maybe it ate one?? Can't find anything in fish books. Would it be safe to use a fish medication like Maracyn2? Thanks very much for any help.