I just got a powder brown tang the past Saturday. Been keeping a close eye on him. I noticed tonight that it had white spot. I'm guessing velvet. Did do a fresh water dip. There is no labor breathing yet so I hope I caught it soon enough. I put in Fritz copper safe. Just a half dose tonight. Plan on doing another 2 ml in the morning. I hope I caught it soon enough.. just glad I put it in a second tank that I keep chocolate chip starfish in. I moved the starfish to the sump of my DT. My current copper level is 1.0. test kit I'm using is salifert copper test. Any recommendations on what else I can do? I also keep the water at 80 degrees.