Damn annoying hippo tang

[Quinster]

A friend of mine had a hippo tang who showed the same characteristics as yours...some days would look fine others covered in white spots, he tried all medications, freshwater dips, cleaner wrasses and shrimp, nothing cleared it up. He had the fish 5 years in a 90G and the fish over doubled in size and never showed any ill effects from the spots upto the day he tore down the tank and not sure who eventually got the fish....don't know what the moral of the story is but it looked good some days ...bad others...ate like a pig and grew pretty fast.