Ive breed convicts for feeders for about a year now. I have a monogamous pair of convicts that shell out plenty of fry to keep me in feeders and I have used the following methods to feed them.
1. The parents take care of them, as both male and female are fantastic parents
2. Crushed flake
3. Crushed cichlid gold
4. Bloodworms (frozen)
5. Daphnia (frozen)
6. Brine Shrimp (freeze dried and regular)