GT Issue - What to do?

[kcinimod]

I have a GT in a 135g that's also occupied by a pair of breeding convicts. The GT has been fighting the male on a regular basis.. been a few months now. Nothing major has happened until this afternoon - His left pectoral fin has been frayed/bit/chomped on and is rarely used. It just rests on his left side.

Pictures are below - what can I do to keep his fin from getting worse - without removing the convict?

http://i34.photobucket.com/albums/d120/kcinimod/119.jpg
http://i34.photobucket.com/albums/d120/kcinimod/126.jpg
http://i34.photobucket.com/albums/d120/kcinimod/129.jpg
http://i34.photobucket.com/albums/d120/kcinimod/117.jpg

 

[Freshwater Tim]

Partition the tank if you can.

Give the parents their own space!

 

[kcinimod]

Should I add anything to the water?

 

[sick_lid]

Should I add anything to the water?

Dither/target fish