Help ID FISH Illness

[JFLU]

Hey guys could you help me ID what my fish has going on with it.
First off I QT all my fish but when I add the 2 new tangs my powder brown started to develop this on it. After about a week and a half. He is still aggressive to the new tangs.

I really hope this isn’t Brooklynella but that’s what it looks like to me. if so idk how I got that getting the fish through qt after a month. Smh

 

[fishywishy]

Do you have any better pics under white light? It’s kind of hard to see.

 

[JFLU]

Here the best I could get with out he or she swimming away