Angel fish white spots? or coloration default?

[aquatic-life]

Hey guys hope you are all doing fine!
i recently bought 4 angelfish and once i wanted to add them in my aquarium
i saw that one of them have small white spots on his tails.(in the pet store :3 angel fish were taken from an aquarium,and the one that i saw spots on it was in another aquarium with other angelfish,but they were all in the same water bag when i got them home)
Anyway,I introduced the 3 in my aquarium they are all doing very well!
As for the remaining one i put it in a 30L. with salt+sera costapur treatment.
it has been 5 days now.. and these spots didn't disappear! Also the fish doesn't look sick at all not quick breathing....
I am doubting that these spots are part of his patterns?
here are some pictures what do you think?