So bettas might actually be part of their natural diet,have you considered or tried earthworms?These lizards are vitually blind and very slow moving. Goldfish and minnows nutritionally are not adequate because of the thiamase issue. They are also too fast for them to catch. Bettas and other labyrinth fish are indigenous to where these guys are found. There are no care sheets for these and people who do keep them are very secretive about them. It's always a learning process with this species every day. Just doing my part to gain a foothold on the understanding of these reptiles...