Yellow tang - brown spots

[Cheetah]

I picked up a large yellow tang a couple of nights ago.

I noticed though it has a small brownish close to black spot on it's side. It's directly under where it's side fin touches it's body.

The spot is blotchy with a straight line of brown right above it.

He's eating and the only odd activity is he's rubbing that side against the rocks and sand every so often.

Tank parameters are perfect, with a small cyano outbreak.

Any ideas?

 

[Billy the kid]

Are you running carbon?My tang did the same thing and soon after there was a ick break out...

 

[Cheetah]

I am running carbon in this tank. I'll pull it out tonight.

Anything else I can do?

 

[Cheetah]

I checked some more online and what he has is definetly not black spot disease.

I'll give him a fw dip to see if that helps.

 

[metalyx]

Check your NO2 and NO3. My trates spiked and all of my guys where scrubbing in the sand.

 

[Billy the kid]

FW dip will take care of the po.