Fish With Black Discoloration, Wound

Hi,

This might be hard to see as he won't pose for pictures, but this fish has what looks to be a small wound and then some rather extensive black discoloration. There's no puss or bleeding, nothing trailing from the fish, nothing in the way of anything similar on amy other fish. Any ideas what the cause and the cure might be?

Better pictures attached. No idea why they're sideways.

Thanks for all the answers, everyone! The situation resolved itself.

I'd certainly be interested to know what happened...did that blotch just disappear?
 
I saw your original post, but I have never made a study of fish disease beyond a few issues, so I will not guess at diagnosis/treatments which can be far worse than doing nothing.  I was waiting for some members with more knowledge in disease issues to comment.  I have had fish with odd black areas, have one presently in fact, but they don't look anything like your fish.
 
Byron.

sorry .. I didn't know what it was either which is why I didn't comment