tiger barb ?ulcer

[millym]

hi
one of my juvenile tiger barbs has a patch on her side that looks like a scale or 2 is missing & looks like there is some sort of lesion there.......its hard to work out exactly what it is as she doesnt stay still for very long.
any ideas or suggestions i dont want to isolate her unless i really have to as barbs are so skittish i know just trying to catch her would be a major drama, ive been putting melafix in the tank but has anyone seen this before??? sorry if my description is a bit vague ive tried to get a pic but failed miserably!
please dont suggest antibiotic treatments as we cannot get them here in the uk without a vets prescription
thanks

 

[black angel]

Maybe one of the other fish bit her, its common for barbs to get rough with each other. Keep an eye to make sure it doesnt get worse and watch for aggression.