Jim Anderson wrote:
In article .com,

Just my opinion - the hump in the forhead suggests this is a young male.
some AF will mature and start mating at around 6 months. The other 2
have paired and are trying to drive this male out of the proposed mating
site. All of the injury areas appear to be fish bites. If I'm right, the
pair will kill him in about 3 days to a week, then start mating.

No, they're not fish bites. That is a fast-moving skin infection. I
didn't reply earlier because I'm not sure what it is and was hoping
Frank would chime in. I could be wrong, but I think it's Costia. The
other possibility is a bacterial infection, but I don't see any
reddening or inflammation in your picture.

If Frank or NetMax also think it's Costia, treat your fish with a
formalin/malachite green ich medicine and watch the other angels
carefully. If you're not sure, use something a bit more broad-spectrum
like acriflavine or eSha 2000 if you're in Europe.

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