I use King British flakes, Hikari algae wafers, two types of sinking pellet from a seller on eBay (one algae based, one more meaty), freeze dried blood worms, a variety of frozen stuff, every so often, live blood worms and fresh cucumber for my plec.
No particular favourite but my Corys go particularly bonkers for the Hikari wafers since I've introduced them.
Cheers
Danny B