Mine didn't eat well for at least a week after we got him. He hates the pellets so I gave up on them and give him a flake food twice a day. He loves the bloodworms and would eat them all day long if I let him but I only give him 2 bloodworms on water change day for being a good boy while I mess up his home
I have found that mine eats better when I turn off the filter while he is eating. Otherwise the food moves around too much and eventually falls down before he gets to it.