I just bought some of these little dudes and im obsessed already. What can i feed them exept leaf litter and bat guano?

I'm not super new to the invert hobby as i've kept a jumping spider before but after she died (rest in peace) i wanted another invert that wasn't a spider. I stumbled upon Cubaris Sp Penguin isopods , did lots of reasearch and bought them. OH MY GOSH I DID NOT REGERET THAT. The little dudes are so silly and i love watching them. Regarding that, is there any things i can feed them , excluding leaf litter?