I feed mine light... and anything it grabs from the water column during feeding time.
Anything fishy and meaty (clams, shrimp, fish, mussels) works. Make sure it is fresh. But as long as you have adaquate lighting it really isnt needed.
You say fresh? Does that also include fresh frozen?
I try to feed mine small pieces of shrimp but he never seams to eat it. He is under 22.000 kelvin t5's