Bought a small Naso, won't eat

[Delphinus]

Well, best of luck. I have no idea how naso's are but generally I've found that with most fish that I've had, that it usually takes a few days to get used to the new surroundings and start taking offered foods.. So a few days may not be all that unusual (I'm speculating), but yeah, if it's been since Saturday.. he has to start eating sooner or later... good luck.