Blotches on Kole Tang's pectoral fin

[Deinonych]

I have a Kole Tang that has been in QT for 4 weeks now. He did not respond well to Cupramine (stopped eating), so I have been observing him instead of treating. I noticed some blotches on his right pectoral fin today. I can't tell if this is ich or something like lymphocystis. I want to be very sure before I start him back on Cupramine. He is active, breathing normally and eating well, and I don't see any spots on the rest of his body. Apologies for the low quality picture, but he moves around too much to get a good shot.

 

[Deinonych]

Bump. I'm going to run him through tank transfer just to be sure. I don't want to risk exposing him to copper again since he did not tolerate it. He's still super-active and eating well, but I don't want to take any chances.