These types of eels really go for worms. You should begin hand feeding it using some live CBW pinched between your fingers. I think you'll find that in no time at all, when he sees you he'll be begging to be fed.
A word of caution - I've a friend with a 2 and half foot fire eel in a 240g tank. The eel will not eat unless my friend hand feeds it. The fish has become so conditioned to this that he keeps schools of tiny tetras in the tank and the eel doesn't bother them at all. It's really the coolest thing.