Its important that you start feeDing them once they start free swimming.
If you have a cycle sponge filter, java moss with some Detritus in it, or Decoration with biofilm or algae on it, the fry will have a munch on the little bits of algae anD Detritus they finD.
Convicts usually make amazing parents so you really Dont neeD to seperate the fry until the parents start to spawn again or the parents start picking on the fry.
They are too small for for the brine shrimp atm, but the first bites will work great. What I Do is I make a mixture of DecapsulateD brine, nls fry formula, spirulina, axsthanxin powDer, anD DrieD krill, throw it in a coffee grinDer, mix it with some water, anD gently shoot the mixture at the fry with a turkey baster.
Works like a charm!
Once the fry are about a month or less DepenDing on how fast yours grow, they are reaDy to eat flakes anD brine shrimp
GooD luck!