Snowflake clown sick

[TommyP]

Hey guys. I got this fish a little over 2 weeks ago. He was mated with the larger snowflake clown. The past couple of days he wasn't eating. He was breathing really heavy and swimming on the opposite side of the tank he normally is by. His breathing has improved since however his fins look damaged. What is wrong and is there anything I can do to save this fish. I drip acclimated them both together. They are the only fish in my 55 gallon tank. The female clown is fine. They both ate cyclopeeze / brine shrimp / mysis shrimp & pellets. Now the 1 healthy clown is only eating pellets & cyclopeeze. The sick clown as pictured has not eaten in about 4 days.
My parameters are as follows:
Temp: 79*
pH : 8.2
Ammonia: 0
Trites: 0
Trates: 5.0
Calcium: 440 mg/l
Kh : 8 *dkh = 143.2 ppm
Phos : 0-0.25 it's really hard to tell

I have to do a water change. But my levels look pretty good besides that.

 

[TommyP]

Any ideas? I skimmed through my tank earlier this morning before I left for work and I didn't see him. Lights were off though. I hope he's okay. Any input would be greatly appreciated.

 

[Flaxon-Waxon]

Could be gettin his butt kicked by the other on with the environment change...

 

[TommyP]

I'm sure a lot happens during my 12 hours I'm not home but whenever I'm watching the tank they have never fought.

 

[Ausfish]

It looks like something is nibbling in his fins. If it's not that, then it's probably fin rot