I'm having the same problem. I got a Peacock Eel about a few days ago and have yet to see it eat my Tubifex blood worms I'm putting in there for it. From what I've read on here, they prefer to eat in the dark. People also say that they feed them with little feeding claws so they can release the worms right in front of them instead of feeding them on the surface. I'm going to buy a feeding claw and try feeding him at night. I'll come back on here and let you know what happens.