Need some help ID'ing a problem


New member
I've had this hippo tang for about 2 months now and a few weeks ago my wife noticed him starting to get dark spots on his brow and forehead and he was rubbing up against the rocks. Within a couple of days his belly was completely white and starting getting light blotches all over him.

I immediately caught him and his yellow tang cohort and got them into my QT tank. I've been treating w/ hyposalinity and Copper for about 2 weeks now and although most of the white is gone and the fish is acting more normal, the dark legions on his forehead are still there (see pic below).

I had assumed because of the white spots and blotches that the fish had ich (given the treatment chosen in QT). However with the white gone and the fish less stressed, those dark spots are still there making me think that something else must be wrong with him.

Any help would be appreciated. I don't want to leave these guys in QT for much longer than I have to given my QT tank is only 30g and these tangs are bit too big for that small of a tank.