Definitely, bloodworms are a good option. If it hasn’t been in the tank long, then it might still be adjusting. Generally, they can be very hard to get eating. I have three fire eels. The first two were easy as they pretty much went crazy for bloodworms from day one, when they were 4”. Those two now eat pretty much anything but pellets. My third one didn’t go as well. I got it at a later time and I couldn’t get it to eat anything for nearly two weeks. Finally, I made a last ditch effort to find something it liked by pretty much shotgunning a bunch of different stuff at once. I mixed up frozen mysis shrimp, frozen market shrimp, frozen bloodworms, live red wigglers, frozen tilapia, and a few others, and threw them all in at once. He ended up picking through and eating all of the red wigglers, so that became what I fed him. He now eats everything but pellets also.
How long has the eel been in the tank?