You can use a starter culture or Jungle brand Little Fry Formula to get you started. Within 48-72 hours you should see a milky cloud develop in the water, this is your infusoria colony. Two tips, always use dechlorinated water and never use a metal container to grow infusoria. Infusoria can be fed by using a small siphon or basting bulb to remove about tablespoon of infusoria laden water. Adjust feeding to size of fish, and be careful not to over feed.
Micro worms are nematodes that are just barely visible.
They are a good source of food for fry and very tiny fish. They are easiest to use in glass bottomed breeding or hatchery tanks as they do sink to the bottom. We culture our microworms in 2 deep Tupperware dishes, but butter containers will work. The container is covered but has small ventilation holes. The recommended culture medium is a soupy mix of Gerber s Dried Baby Food , water, and a pinch of yeast.