A jar of Moina (small Daphnia), 50 g active dry yeast, 50 g spirulina, all in a container that would be a good Moina culture container! I can also include green water if you want. You can feed the Moina green water or yeast and/or spirulina. I fed it a 50-50 mix of yeast and spirulina over the winter; I noticed that it multiplies more rapidly on that than on green water, probably because the food is more concentrated.