What non live food do you plan on feeding them? Have you experimented with varieties of food? Try market shrimp. Cut them up into small pieces and drop them in the tank. See if they will accept it. I am sure they will because thats how I got all my datnoids to take non live food. Pellets are tricky. Two of ten datnoid's I have eat pellets because they were already trained when they were still young. With pellets you can starve them until they give in on the pellets.