Yeah, I lauged pretty hard at that earlier this morning. My little map turtles (about 5" in diameter) will tear up some feeder fish. These turtles are ALWAYS hungry and will devour just about anything tossed in the tank.
They hit "rosy red" feeder fish with such force and precision that I've seen them bite of the back end of the fish, clean in half, and the half with the head keeps on swimming off for another second or two until the other turtle slams it from the oppoisite side and then there's no more fishy.
I've never thought of earthworms. I'll have to try that.
They love ghost shrimp.
I've even fed them baby crawdads (or crayfish if you're a yankee 😛). That was FUN to watch, the crawdads fight back. I couldn't feed adult crawdads to them as they could hurt the turtles at the time.