It isn't necessarily brands that you need. It is more of what variety do you need. I was asking this question about two months ago when I was embarking on an attempt to breed swordtails and mollies. I was told to have a good variety to promote fish health, growth, and color. I feed my fish frozen shrimp every day (obviously warmed up), flakes by Tetra (My fish don't like Aqueon's flakes for some reason), an algae wafer twice a week. Sometimes I will give the flash frozen crab bits. I also has shrimp pellets for my cory and otto. If the platys are young which I am assuming because you want them to grow faster try to find a product called First Bites. While many say it is just ground up flakes I feel the fry I have feed it too have grown faster than fry I had before that didn't get fed the First Bites.