What is on the face of my clownfish

Bought a couple tiny baby clownfish (very small) a couple weeks ago. I have noticed this white mark on one of their face which was not there when I bought it. The other baby clown looks like it may be starting to get it also. Any help letting me know what it looks like would be greatly appreciated. They eat and act healthy. No ammonia, nitrite, and alkalinity is good also. Clowns are hosting richordeas and euphylias,but doubt they are stings from coral. Looks like bacteria or fungal. Had issues in the past and made the tank "semi-fallow" except for my mandarin and pipe fish. Had funky crap happening before and now thinking it wasn't truly fixed due to not being truly fallow. Please help.