My Guys recently started taking pellets along with frozen krill.. people will argue but I don't personally believe in starving my fish to get them to eat what I want them too. To take the pellets I've been soaking them in with the frozen krill to pick up the scent/taste. It's taken a few monthes to get them readily accepting the krill, and only a few more weeks to add pellets. Have patience and be persistant. I also would suggest using a sinking pellet, and make sure the pellet is smaller then you think they can easily handle. 20" eel takes the medium Hikari excel pellets after pre-soaking with abit of hesitancy still. Getting it to eat from your hands also make it alot easier ot introduce new foods to them, they will usually be curiouse to try anything you offer with your hands once they associate it with food.
Steps.
1. Get onto frozen food ( usually longest step)
2. pre-soak pellets with frozen food ( frozen should always be thoroughly de-thawed before feeding anyways)
3. Mix it up ( Mine still get nightcrawlers, the krill, and more and more pellets.)
I personally shoot for a 60% pelleted/pre-made diet and 40% frozen/live diet. For all of my fish. Summer monthes usually end up more live foods ( worms are alot cheaper) and winter lean more on the pelleted/frozen side.
I also browse my local seafood counters for deals on shrimp ect to try and add more variety to their diets ( And sometimes a snack for me =D )