You don't have to be all that creative with what you feed them. They'll eat just about anything your fish eat, including flake and pellet foods.
I personally like to give mine a little variety just for the heck of it consisting of pellet and flake food once a week or, if I'm feeling motivated, a mixture of mysis shrimp and cyclop-eeze merinated over night in a little bit of salt water and selcon (they love it).
I mostly just feed my ricordeas, but once in a while I'll feed a couple of my discosomas as well.