I feed my peacock eel (Macrognathus siamensis) live earthworm by putting the earthworm in a plastic tube and dropping it right in front of the peacock eel. Once the earthworm is picked by the eel, no other fish (rosy barbs, tiger barbs, arulius barbs) can get the worm away from the eel. I just make sure the rainbow snakeheads (Channa bleheri) that are in the same tank have also been fed their share of an earthworm so that they won't grab the worm away from the eel.