What the heck is this on my tang?

[K7BMG]

I guess your not believing its just scuffing from being chased around.
If you are seing something we cant in the pics and video then yes pull him out and back to QT.

What time frame are you talking about here?
In minuets or hours?
Velvet is the only thing I know of that can be seen and kill in a few hours.
This is not velvet. Velvet is not rough and puffy.
No other bacteria or parasite will present from nothing to that in a few hours.
The only thing could be an allergic reaction to something, or sting from a coral that would present so fast.
But again what time frame are we talking here?

 

[gobble]

I'd say I didn't notice anything during quarantine or when the fish was being acclimated and I first saw it about 30 minutes after it went into the display. For those first 30 minutes it was hiding in the rock.

 

[gobble]

Whatever this was seems to be going away. I'm guessing just rock rash from his dash into the new tank.