Angelfish with white patch!

[Fishyflash28]

Hi, first time post but long time reader. My little angelfish has happily been begging for food and swimming around the last two weeks I got him. I slightly over fed him as he bloated up some. I cut back on feeding and he’s back to his regular shelf. However I noticed a few fuzzy white patch developing on his back the last few days. He gets chased by another angel from time to time but they hang out together often. Just want to do the best thing for my little fish if something is wrong or if he’s just adjusting to my tank. Paramitors are steady but ammonia jumps from 0-.25ppm, nitrite solid 0, ph is 6.8 and nitrates 5-10ppm.
My other angel and corys are happy and show no signs.

Thanks!