thanks all, i bought him some aquarian brand color enhancing pellets. (for the high protein content) the first time he ate one, i could tell he was having trouble with it. he kept doing that little "chewing" thing that they do, over and over. and then he looked sort of dazed for a while, and kept opening and closing his mouth a lot. finally, he sort of spit up, and little gooey parts of food came out of his mouth.
i think it may be because i didn't soak them first. :o i'll do that for sure next time.