Firefish left side of head looks raw?

[Nierika]

The left side of his head has a patch that looks kind of raw. There's also pink on the other side but doesn't look the same. I'm not sure if it's an injury or something else?

 

[Frtdrmrose7]

Is this a new fish? That could. Be severe ammonia burn in the gills. Is he breathing fast? Any symptoms? If he is new how did you acclimate him?
I would start with a methylene blue bath.

 

[Nierika]

He's been in the tank for about a year now. It's a 90 gal with plenty of live rock. I just tested ammonia with Red Sea just to be sure and it came back 0. He's eating fine and seems to be acting normal. I'll check his breathing once the lights come on.

Everyone in the tank gets along for the most part, although the Cardinal will chase him occasionally (but I've never seen any other aggression between them)

The hole he sleeps in is only slightly larger than he is and he darts in and out, so I wast thinking maybe he miscalculated at some point.

 

[Big G]

The hole he sleeps in is only slightly larger than he is and he darts in and out, so I wast thinking maybe he miscalculated at some point.

Yep mine get that constantly and they occasionally tear off their top fin too.

 

[Nierika]

Yep mine get that constantly and they occasionally tear off their top fin too.

My Coral Beauty is such a spazz, he's always got random chunks taken out of his head