Good list of foods posted so far.
Most people say ewwww about this but I breed Caribbean lobster roaches, my yellow mud goes nuts for them. He also goes nuts for the meal worms I breed but because of the chitin I don't feed those to him very often.
He loves any live thing I toss in, so I try to give him the widest variety of live insects, earthworms, & fish that I can.
He also likes some of the frozen fish foods that I thaw for him such as bloodworms & brine shrimp. I tried plankton, tubifex worms, & glass worms, he wouldn't go for those. When it comes to greens if I make turtle food with greens hidden in it he'll eat that, otherwise it's hard to get veggies into him, but he is a yellow mud not the same species you're looking at.

Good luck with your new turtle, let us know when you get him/her.
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PHRatz