Salfin white spots

[HOLYREEFER]

Can someone help me ID the white spots on this salfin Tang? I currently have him in QT

 

[Big G]

Is it in copper or other meds?

 

[HOLYREEFER]

right now in neither. He’s just in quarantine tank.
It looks more like scaring than an actual issue. I’ve been feeding Dr g‘s medicine frozen and it looks to be doing just fine. Ill continue to monitor it over the next 5 weeks prior to being put in the tank