My powder blue tang has gone through copper, prazi pro, and is about to be done their 21 day 1.009 sg hypo-salinity along with a blue tang/wrasses. It still is going to be 4-5 more days on hypo but I am not sure on why it is still scratching. It also seems to have 2 white marks on its gill area. Does not look very much like ich or velvet though. Maybe just damage from scratching. It eats like a pig and is a great fish except for the scratching . Any advice would be great.
