? about spots on my tang

[hawaiian_boi]

i got this sailtang 2 months ago and he was fine.. a week or so ago i noticed a white spot on its tail when i was feed him. the next day it was gone. the day after that there was three spots.. then gone.. so yesterday while cleaning the glass i was looking at him.. he eats like a pig but looks kinda skinny. so today when i the lights came on i noticed a whole lot of littler white spots ... i have no idea whats wrong. is it ich? dose it apear and disapear over night.? what do i do?

i also have a clown tang flame angel . the clown tang and angel dosent have any white sopts on him . i have the sailfin the longest.

 

[SmknReefer]

+5 ich as tangs are notorious for ich. QT all because the ich won't leave as long as there are fish.