thanks so much. you are the only one to reply lately. As someone suggested a while back, I gave the tank a treatment of prazipro just this week. That is for many types of worms etc. It says not to use any other treatment in conjunction with it. Isn't melafix for bacteria? I tried pimafix for fungal. and melafix. Also Lifeguard All- in- One and 'Parasite guard' both from Tetra.I may end up kiilling them from treatments! The fish don't seem to be suffering yet - good appitite and lot of swimming around. So I will decide at the end of this week if I sould try another treatment or retry one or as you suggested just let them try to fight it. The nitrates and nitrates were off the chart when I first saw this but the parameters have been perfect for a month now. Maybe that will help them fight it. so far 2 fish never got 'it' and 2 do. One is pretty bad but he is healthy otherwise?
kind of a long ramble isn't it