Injury to Disease?

[Calihawk]

I recently sold a Flowerhorn, I was told to hold him a week before shipping so in that time he managed to injure his left gill plate...possibly on the egg crate divider. Now the buyer is saying that it has a disease on the left gill plate.

I kept 6 Flowerhorns in a 55gal, each seperated with acrylic divider, with 3 different filtration...and none of the fishes are new (5 months together). I feed no live food, only pellets, I have bags of zeolite and carbon at the bottom. I have a pleco that rotates from one section to the other to clean algae. All the other fishes in the 55gal now, do not exhibit anything like the injury to the flowerhorn.

I'd like anyones input on this matter:

 

[Calihawk]

"Here is a photo I took yesterday- both holes are through the gill cover now and you can see the gills underneath moving. There are several spots starting on the end of the body near the tail. I am a big believer in the salt treatment too, but doesn't seem to be working. He had a dip in methylene blue today- not something I've ever done before but recommended by the local fish store. He was eating, but not for the last two days. He doesn't look happy anymore. I will get more pictures..."