Injury or Disease? Gold Barb on the brink!

[Quartermain]

I came home for lunch this afternoon to an unpleasant surprise. I found one of my Gold Barbs in the condition you see below. The fish has large ulcered white patches over its body and it's left fin is nearly completely gone. This must have happened virtually over night as the fish seemed perfectly healthy the day before. Or the signs were too small for me to have noticed.

I have had fish with fungus (white tufts, like wool) and treated them successfully. But I think what I'm looking at are dead scales, not fungus. Since this is a semi-aggressive community tank with Barbs and Gourami's I have to consider the possibility that this is an injury caused by fighting.

Does anybody share the opinion that this is an injury and not disease? Or if it is a disease you're familiar with what's the treatment?

You're help is extremely appreciated!




The same fish just days ago.

 

[Dangerdoll]

definitely looks like an injury to me....

 

[Quartermain]

That is consistent with the speed at which it came on but then I don't have any experience with Columnaris or other bacterial infections which have symptoms that are at least similar in description to the pictures below.

Just out of curiosity does anyone have a picture of Columnaris? Google has a few but they're very low res and not very clear. Or can we be clear that this is not Columnaris?

 

[Quartermain]

I suppose I should inform you that the fish died last night, but its still a mystery as to why. I first noticed the legions on Wednesday. I quickly sequestered him in a clean 5gal bucket with aquarium water, heater and airstone. After consulting the web and AC, I decided to dose Maroxy and Melafix. His condition remained unchanged overnight. However Thursday when I returned home from work the legions were noticeably whiter and less transparent. The legions had not grown in size and there was slightly less redness around the edges. I took this as a good sign. But his body was clearly swollen and you could tell he was stiffening up. He died sometime during the day on Friday. I've brought fish back from the brink before, but only when I knew what the problem was. This has been a healthy tank for so long I'm kind of concerned. I'll be watching the other Gold Barb and the other fish for any signs of stress related to whatever this thing is.