well I know nothing about pyxie frogs, but i do know that a lot of the tadpoles diet can be found from the shape of it's mouth. That being said, a lot of times people use either the standard fish food worms or brine shrimp for surface to mid level feeders, with a lot of people using frozen lettuce or algae pellets as the main staple. Mind you I haven't kept amphibians in years, and I could be wrong, but I hope this helps.