so far we have:
1 blackworms
2 daphnia and mosquito larvae
3 brine shrimp
4 other shrimp, feeder fish, micro/walter/banana worms
5 vinegar worms
6 grindal worms, red wigglers, superworms, bloodworms
7 tubifex, crickets, salamanders, newts, beetles
as for me I like to give them: blackworm, daphnia, mosquito larvae, and walter worms.