Just within the past week, my green severum developed a strange disease all over this head...Part of it looks like the begininning of HITH and the other part is like warts...No other fish in the tank have anything like this. It just appeared over night basically. I don't know aht to do to get rid of it. I bumped up the heat and added salt, but I can't add meds since the tank also has catfish in it.