[rmlevasseur]

yes, based on your description and some clowns I recently had with broolynella, i'd concur with leebca.

However, I don't agree that QT and antibiotics is the only answer at this point w/o a clearer shot of this fish. If it is still eating, I'd rule out the other non-disease related possibilities first. Leebca very well might be spot on, but if the fish is still eating and the other fish don't seem affected, I'd try some treated food and perhaps removal of the coral banded first. If you do have a diseased tank, all the fish might need QT, and the display would have to run fallow for quite a while to remove the disease. Probably not a step you want to make hastily.