Emerald Green Corys noses

[Fresh808]

I have 6 EG Corys in my 75 with the convicts and Oscar and red tail sharks. I noticed one of them has what looks like a war wound on it's nose and though maybe it got too close to the pair of convicts with fry. Now I see there's another, but not as bad, but it's a small white area on it's nose like the other, but smaller.
Anyone have an idea it they are prone to tissue issues that might appear in this area or is it more likely that they got too close to the male convict?
He bites me hard enough that he broke skin between my fingers this evening so I know he could inflict damage on the smaller fish if he wants.
Aloha,
Scott

 

[fort384]

I would tend to think it was aggression, as you suspect.

 

[Fresh808]

Oh, and one maybe two of my emerald Cory cats has these white patches all over their body like someone with that skin pigment disorder. Sorry, not sure what it's called, but how about that for complicating things. Should I relocate these corys till I can get that under control? Don't really have anywhere to put them except for a bucket.