White Mark On Fish Gills

[jaymie777]

Hello everyone i have a green terror and have noticed some weird white mark that has come on the edge of his gills.

here is the picture

i have been trying to figure out what it is and think it is Columnaris.
if anyone can give me any suggestions or let me know what you think it is, or any treatment advice
thanks
jaymie

 

[Lupin]

to MFK!

What decors do you have? If you have abrasive decorations, then the gills may likely have been injured. Isolate the fish and give it daily water changes by at least 30% until the gills recover. If this persists after a few days, administer a combination of Maracyn and Maracyn 2.