What's on my tang??

[Luke Schnabel]

I bought a powder blue tang two weeks ago and it's been in my QT tank since. I have a 30gallon tank I use for QT. SG 1.025 and Im on the last days of using prazipro. I just noticed today my tang has a brown spot on him. Also has cuts in his fin which of from the other tang and him fighting in the QT tank. I went the way of getting both tangs at same time like a lot of people suggested but I'm going to get rid of the other and end up getting a different tang later down the road. I've been looking all over the net and everything seems to point to stress.

Can anyone help ID this.

 

[Newsmyrna80]

If you are referring the spot on his dorsal it appears to be a stress marking. Does he have somewhere to hide and get away from the other tang?

 

[Luke Schnabel]

Yea I have 2 big pvc pipe elbows that they hide in. It went away a little bit today. I'll be taking the other tang out as soon as I have a day off.

 

[Deinonych]

Looks like battle damage (bite wound) to me.