Has he/she spit water at you yet?? lol
I know of someone who feeds theirs any type of insect/creepy crawly pretty much.. flies, spiders, crickets, mosquitoes, grasshoppers, beetles, cockroaches, meal worms, earthworms and like with most fish you can train them to get onto pellets but only if they float.. most seem to not be too interested in foods that hit the bottom.. so anything that floats I'd try it!