It is a stressed out Naso lituratus.
It shows no signs of being malnourished though. Just stressed. Probably from being recently handled. Like being captured and stuffed into a bag and transported, or being in a small or otherwise stressful situation.
Just make him comfortable, keep up on those greens, and he'll likely be fine.
Peace
EC
Yes, funny how that seems to escape so many. When naso tangs are that small, regardless of the specific species, it can be difficult to identify them. For anyone that has actually kept a tang in the naso genus, those white blotches are very common in a stressed but not necessarily diseased fish. It is possible it is a very unhappy lituratus, thought the head coloration is usually apparent even at that size/age. It's not a bluespine (N. Unicornis) because the blue tail base is also usually apparent at that age. I'm sticking with brevirostris, though vlamingi is a distinct possibility.
Guys, thanks for all the quick responses, he was very stressed I took those pics right after I put him in a new tank with new tankmates.
He is doing much better today, he is eating and spots are gone.
here are some updates pics
what do you guys think now?
It is clearly Naso lituratus. That last pic should clear up any confusion. Great fish. Intelligent, friendly, and easily trained. Not bad to look at either.
Peace
EC