The only fish I've had that continuously get sick are mollies. Now I have a white molly that has swim bladder disease. I've had 4 Mollies before her that have gotten really sick. I've fed her peas, parameters are 0 Ammonia, 0 Nitrite, and 20 Nitrate, tank mates are 2 Angelfish, 6 Bronze cories, 5 Nerite snails, another molly, a guppy, and a clown pleco. Can anyone tell me why I can't keep mollies correctly? I know they like brackish better, but I've read that they can successfully be kept in fresh.