As well as prepared foods, AQUABITS also provides Live Cultures so that you can grow your own.
Daphnia is a common and natural food source for all kinds of fish, which activate your fish's natural instinct to hunt it's food. Daphnia, being alive water bug, will also not foul your water quality, and will live in your aquarium until caught and eaten by your fish.
There are many instructional videos and guides online that can show you how easy it is to grow your own Daphnia population from your starter culture.