I feed mine freeze dried bloodworms, so you're doing better than I am
In the past I've fed earthworms and tubifex worms as well. I'm sure the'd probably eat feeder guppies too.
Mine loved tubifex! Also liked frozen:mysis, daphnia (left the cube to defrost in the tank, the cube sunk and they just bit it and threw it everywhere), mussel and beefheart every so often