Both! I actually feed my African fry crushed flake food with spirulina. Basically anything that tastes good and that will fit in their mouths should work. But a mixture means they get the nutrition from both.
When I first started out breeding fish it was with guppies and I made a concoction of shrimp pellets and finely ground flakes. Went overboard with those little guys, and probably still do with my current fry food for egg layers. Currently its a mix of spirulina, golden pearls, first bites, crushed flakes, and growth meal # 00. Everything excluding the first bites is from kensfish.com. Definitely worth looking into if you want some good food.