IME, it's best to feed a variety rather than just one type of good food.
I'd recommend frozen bloodworm and/or frozen brineshrimp 2-3 times a week, along with some kind of algae or vegetable based flake also 2-3 times a week, and the rest of the time feed a decent all-round tropical flake food.
I wouldn't worry about which brand too much, focus more on storing it correctly. For example if you buy a really big tub of something, separate maybe a months worth of it into a smaller resealable tub for frequent use and freeze the rest of it. I'd personally try to avoid the big bags of value flakes unless you know they are relatively fresh.
I would avoid the live food that comes in the little bags, I've had trouble with parasites from these in the past, brine shrimp from these is safe though - since they live in brine I cant imagine any freshwater parasites surviving.
If you want to condition them with live food it's safest to culture your on in a tub in your garden or something, literally just leave a small bucket of water with a handful of dirt or some straw in the sun for a week or two and you will have a great supply of mosquito larvae, daphnia and copeopods

. You should feed these to the fish when they are in the breeding tank.