I started feeding new life spectrum pellets exclusively a couple months ago. I previously fed a variety of all top foods, hikari,omega. My fish took well to switching to NLS and everything seemed well until one of my cherry barbs stopped eating. My first thought was that he was sick as all the fish I've lost stopped eating before expiring. Well he didn't eat for a week, didn't really show any signs of disease except he was quite as red as the other barbs. Well something crossed my mind to try some of my omega one flake food. Next thing you know he realizes it's flake and not pellets and decides to eat. The next couple days I go back to NLS pellets and he didn't eat. Back to omega one and he decides to eat again. Will a fish just go on hunger strikes that if they get tired of certain foods? I guess I'll be going back to variety . I have about 30 fish in my 55 gallon and he was the only one with this problem .