Hikari is amazing. I know a lot of people harp about the ingredients in it, or it's expense, I swear by it though. I've never seen another food bring out the colors in fish so well. And I know it sounds crazy, but I swear that fish just act... happier on Hikari.
The only other food I trust is Omega One. I've got my kissing gourami on "Super Veggie Kelp Flakes" because she spits out anything else. My two baby goldfish are on Omega One's pellets, because they're the lowest protein goldfish pellets I've found. I'd put them on Hikari in a heartbeat, but I had read that protein contributes to wen (head) growth in orandas, and to tell you the truth I don't want these guys to have ginormous heads like show fish do XD