What is going on with my tang's fins?

[dismayed]

So I have a sailfin tang in quarantine. He had ich all over his body and on his fins. I started treating him yesterday with Cupramine (copper) and followed dosage very closely.

He seemed like he was doing better last night. This morning I wake up to find that I don't see any more traces of ich on his body, but he is looking really bad now. His fins look shredded, like streamers. What is going on? Is there anything I can do?

 

[Percula9]

He is probably suffering from secondary bacterial infection. He needs antibiotic treatment. He has no visible ich because the cysts have fallen off and went to the bottom of thew tank to hatch again. When they hatch and become free swimming tomites, this is where the copper kills them. Copper can only kill them in the free swimming stage. Don't take him out of QT. Continue to treat him with copper and antibiotics.