Microworms are actually nematodes.  They are prized as a fish food for very small fish fry.   Aquarium enthusiasts use microworms as a food for a variety of fish and crustacean species including:  Corydoras, Tetras, Rainbowfish, Livebearers, Killifish, Bettas, Gourami, Angelfish, Barbs, Danios and many others.

We have microworms for sale on our site.