Wardly pellets, bloodworms, small bits of chicken and turkey.
The boys get two pellets twice a day, Ariel gets one twice a day crushed as they're too big for her very petite mouth.
Bloodworms are sort of a special treat. They usually get them if they've had to be corralled out of their tank for a water change or photo op. Ariel's gotten quite a few since she came home because she was so skinny and tiny in her dirty little Petco cup. They've helped her put on weight and she's getting less now.
There's debate on whether or not you can give them meat like chicken or turkey (I've heard yes and no) but everyone LOVES it as a once a week special treat and I swear it's helping Jeffery get downright monsterous in size and finnage. Also they all turn into sharks when we break out the chicken or turkey. We get charging, latching on and thrashing, playing with food, and I've been bitten once lol.
Gyarados doesn't tend to eat all of his food, so the ghost shrimp eat up his leftovers.