i would just go outside, dig up some regular worms and throw those in. my fire eels really love those. in fact they dont eat anything else! they are pretty young at around 10" but go totally crazy for worms!
How do i feed live bloodworms? Do i just throw'em in? cuz they seem to sink into the gravel and i don't think my fire eel can get to them...at least i haven't seen him eat any. On the other hand i just saw him moving around with poo dangling out so he must be eating SOMETHING...