My Naso tang is depressed

[rcreations]

Hey everyone, I've noticed lately that my Naso tang looks depressed. He's not as active as he used to be, doesn't eat with as much apetite. Is not skinny and still loves the Nori but regular food I just see him picking at it. My water parameters are great, in fact my nitrates have never been better. I just tested everything before my water change on Sunday and Ammonia, Nitrites are at 0, the Nitrates are 10 and this is right before a water change. I've had him for over a year, in a 150gal, he's about 5-6" now.
My guess is that he doesn't like his tank mates anymore, they've become too agressive. Like when he starts swimming around my queen angel sort of chases him off and so does my sargassum trigger, even my foxface bugs him. But they've all been in there with him all along, they've just gotten big. None do any serious chasing but I think they're bugging him. Not sure what to do.

 

[katsafados]

Put some prozack into the tank! lol maybe that will cheer him up.
Maybe hes being bullied

 

[crypt keeper]

Time for a bigger tank and some new fishmates right? hahaha. In all seriousness maybe he is being picked on and is just like you said. Depressed

 

[rcreations]

Yea, I think he's being picked on just enough to bother him. I don't know if I should give it more time or if I should look into selling him to someone with a more peaceful tank. He's been with me for a while but honestly, he's my least favorite fish.