Ok, one more time. I did administer it by the book (according to Fenner and company on the wetweb media). I had a ph
monitor on the 40 gallon hospital tank 24/7 and all the fish were treated. The sg
was kept at 0.010, checked twice a day and tank temp was kept at a constant. I vaccumed the bottom of the tank twice a day. Was going to continue the treatment for 3 weeks, but in week 2 spots came back and 3 fish died very quickly.
Once the cupramine was put in, the spots disappeared within 3 days never to be seen again. The main was left fallow for 8 weeks, fish were returned and everthing is fine so far.
All I'm saying is that when you have very sick fishes, copper use with a proper test kit is a faster, easier treatment and has been effective for a long time.