Flasher Wrasse losing dorsal fin

[ChadmRoman]

Lately noticed my flasher wrasse losing it's dorsal fin. Prior to going into the DT a month ago, he went through 30 days of copper, two rounds of gen cure, and food soaked selcon and gen cure. I don't see much aggression toward him other than right before bedtime. Out of all my wrasses, he is second in command. the first in command chases him for a few minute before bedtime to let him know he's still the boss.

three feedings a day, one of which is food soaked with selcon, the other two is a mix of dried and TDO.
Parameters are stable at:
Ammonia - 0
Nitrite - 0
Nitrates - 16
PO4 - .1

the only thing I can think of is bacterial since I didn't dose kanoplex during QT. I've tried catching him without any luck, so hopefully I treat in the DT by soaking food with kanoplex to help with the infection, if this is the issue. Any help would be greatly appreciated.

 

[fishguy242]

hi,does look like bite marks, but let"s get some expert help here.
@Jay Hemdal @vetteguy53081

 

[vetteguy53081]

This is a sign of aggression
You will need to locate the culprit
Best way is to prepare a feeding , a time when aggressor is in bully mode
Set up your cell phone to video mode for about 40 minutes and walk away- you must walk away
Come back and review video and you should see who the aggressor is

 

[ChadmRoman]

This is a sign of aggression
You will need to locate the culprit
Best way is to prepare a feeding , a time when aggressor is in bully mode
Set up your cell phone to video mode for about 40 minutes and walk away- you must walk away
Come back and review video and you should see who the aggressor is

Thank you, I think I already know the culprit, but will setup and see if I'm missing any of the aggression.