Picasso in need of your help

[fulmetal]

I am new to the board here. There is a ton of info on this board. Ok for the question. I have approx 6 months on my tank I have approx. 60 lbs of live rock in a 70 gl tank, no corrals just a clown and 1 (now) yellow tang I had 2 tangs but I unknowingly brought in a sick fish a month ago They developed a case of fin rot at the same time the Huma got a few white spots around his horn. So my first thought was oh no not ICH!! So in the hospital tank they went.
As for the real question: All of the fish have been on a copper treatment for 8 days. If you count the days the spots were on the triger in the main tank it is going on around 20 days All of the research I conducted said the spots should have fallen of to hatch around day 3-7. Are there any other things that could be causing the bumps to be there and should go with the 40 day ICH treatment just to be on the safe side? Any help would be greatly appreciated

[ick sucks]

i lost 2 boxfish from copper medication. they died not because they were sick but mostly because i later learned about there skin condition and how weak scaless fish are! scaless fish are very sensitive to copper medication. i assume just like invertabrates are. so do some research on a picasso and there skin conditions.