I think your fire eel just hasn't become comfortable with his new home. I bought one about a year ago. It did the same thing. They're often a challenge to get to eat..my first fire eel died after about 3 months of not eating. About 3 months ago, I decided to try another fire eel. He didn't eat for the first 2 weeks. I finally got it to take tilapia on a BBQ skewer. Now he's a pig. He's growing and swims out and about, even during the day. He's eating freeze-dried krill, thawed tilapia fillets, silversides and shrimp pellets. As with all spiny eels, try bloodworms. It's trial and error with fire eels. I also have 2 tire tracks were slow about eating for the first few weeks. I've had them for a few years and they are true gluttons. As far as the grayish-white underside, was that the original color when you first purchased the eel or has it changed? Fire eels, tend to be a bit lighter on their belly area.Good luck.
