mine is eatting pellets, it is about 14 inches long now. it takes a long, long time before you can get them on pellets so the earlier you start the sooner it will accept them.
Good luck. I gave up on this after several attempts. Maybe I didn't starve mine as long as other people here because I thought that might cause more serious problems than this diet issue. Let's enjoy the fish and keep its natural diet! Plus, pellets are not as economical as one may think when feeding them to big jars. Just my $0.02.