B/W clown, deteriorating lower jaw
 

Hi all,

New to sick fishes. All fish deaths so far have been simple "fine one day belly up the next" cases.

I've had this black and white clown for more then 4 years, healthy the whole time. For the past week, this fish stopped eating, and is hanging out in a corner of the tank. The lower jaw is changing color (lighter) and taking on a bit of a wrinkled appearance. This is getting progressively worse.

I know I should have a pic, but I don't at the moment. I'm fairly sure that bullying is not the issue. My tank is generally peaceful and this is one of the more aggressive fish that does a good job taking care of itself.

Thanks.