Thank you both for the advice. I think it was probably originally an injury which happened when all four dollars were getting a bit frisky, they really throw themselves around in the tank! Looking at it again today the wound looks clean with the top part appearing to be less raw if that makes...
About ten days ago I noticed that one of my Silver Dollars had what looked like a large lighter patch on it´s side with a smaller one above it´s eyes. The smaller one is still there but hasn´t really changed but the larger patch was covered in white fungus a week ago. We treated the whole tank...