What's on this clownfish?

[dive girl]

My friend sent me a photo of his clownfish today. I know next to nothing about his tank except he's had this clownfish for about 9 months. I know that he doesn't QT anything before adding it to his tank but don't know if he's added anything recently.
Can anyone tell me what the discoloration is on the middle white stripe?
I can try and find out the answers if they are needed, but can anyone tell what is on his clown and how to treat it?
He doesn't have a HT or medications, but I do (I QT and have seahorses so I'm prepared for just about anything) so I can send him home with what's needed.

 

[dive girl]

It's not easy for him to communicate right now but here's what he said to a couple of my questions:
Nothing new
Eating normal
Acting normal, except no longer hosting in anemone
Blotch is on both sides, same place
Pinkish in color

 

[mr.clownfish]

my guess would be bacterial infection. copper would help a lot if possible.

 

[dive girl]

Thanks for the reply. He's put the fish in a QT and he's going to do formalin baths every other day for 3-5 days.