What kind of pellets are you feeding? Ive learned that its easeir for me to keep a variety of pellets for the different fish i keep. not all of them eat the same thing. if i only fed one type of food then you would have seen a thread like this one from me a long time ago.
I feed NLS
Massivore
Hikari gold
hikari bio-gold
Veggie flake
Kens growth pellets
kens color pellets
kens krill pellets
soft sprulina pellets
carnivore sticks
And theres a few other foods im going to try as well but for the most part my fish room is like a 5 star restaruant

lol And now that i think about it, my fish probably eat and live better than i do

but i feed them whichever food they prefer consistantly and i mix in frozen krill, shrimp, talapia, bloodworms a couple days a week. Some fish are just picky eaters, andeven if you dont get such a wide variety by starving him like that he'll eventually eat but he may not like it andyou may not get the best results from him as far as growth and color, just my opinion.