My fry is VERY picky...and he is too big/ needs to start growing faster to be eating microworms now...he can fit like 3 in his mouth at a time LOL...I've tried frozen food, crushed flakes, crushed dried worms...*sigh* how can I get him to stop only eating microworms...I have let him be spoiled for too long and I believe his growth rate has been decreased because of it.
I tried my fry out on crushed pellets even though they're still tiny. I found that most of the fry were willing to try the pellet but only half would actually eat it. Start by mixing microworms and pellets (or whatever your feeding) and slowly wean him off the micros. Sometimes you have to use tough love.
I know one breeder who feeds nothing but dried foods. She uses it as a method of culling as the fry who don't learn to eat dry foods die off... it sounds cruel but it's effective.