Help for clown fish

[Thekegk]

Hi all. Been reefing for several years. Just noticed my clown isn't looking good. It looks like she rubbed the sides of it's belly raw. Never seen this before. Any thoughts?

Water is good.
Alk 8.2
Cal 420
ammonia 0 tanks been up for 6 months+
Nitrate >5
Nitrite 0
I had been treating my fish with metroplex for tail rot. Others are looking fine.
Attached a pic

 

[Qasimja]

look up uronema does it look like that?

 

[Big G]

Any other unusual behaviors? Flashing, breathing hard, etc.?

Any aggression in the tank?

Anything new in the tank in the last 30-60 days or so?

 

[Thekegk]

Yes that looks like it. Yea I added a flame angle just over a month ago. He brought the tail rot. I will do some research and start treatment. Thank you for the help!