Fish unwell

[Sammybe75]

Hi I would be very greatful for any input as to what might be wrong with my clown fish.
She is a mocha but went completely black so I was surprised to see her develop this orange patch either side of her top fin. I treated the tank for a bacterial infection.
Shes eating well but the patch is growing?
I also dipped her in warm osmosis water for a minute but no sign of any parasite?

 

[Sharkbait19]

Anything else seem off? Any potential stressors?
I know my mocha started to go pale similar to that, and then it went pack to normal as fast as it came. I had just done a major rescape and big water change around the same time and I think it was related to stress from that.