what corals are you wanting to feed? if it's sps, fish poop should handle that. no need to add additional food.
if it's lps, you can go to the supermarket and purchase an assortment of fresh items, like squid tubes, clam, scallop, shrimp...stuff like that and put it in a food processor. then toss the mix in ziplocks and freeze flat. it's much more affordable than LFS foods, and alot cleaner for your tank as well.
i've been making my own food for years.