Ive had a lot of success pellet training. But as the others have said you have to start when they are very small. Less than 2" if you can. I always use a medium sized eye dropper and squirt thawed blood worms into the tank. The movement triggers them to hit the bloodworms. Once they are eating the bloodworms vigorously (usually takes a few days), I start adding crushed massivore to the bloodworm mix. Let them soak a bit so the pieces get pretty soft. Over several days you will notice they start to eat the pellet bits just as eagerly as they hit the bloodworms. Slowly use less and less worm and more pellet. Also a good idea to occasionally use small bits of tilapia and shrimp mixed in as well. This gets them eating just about everything. I have used the bloodworm / pellet mix and neglected using tilapia and shrimp, and as adults they still will not touch tilapia or shrimp. So variety early and often is the key.