I've always heard they'll eat just about anything you offer them once they're settled. I used to have one that would devour some flake food, LRS Nano, and mysis.
IME, they eat everything you throw at them. They're not picky. Also IME, they tend to be the best foragers post feeding as they like to explore every nook and cranny and they find the bits that everybody else missed. It's part of their robust personality.