Microworm Culture (Starter Kit 100ml)

Microworms (Panagrellus redivivus) are tiny free-living nematodes approximately 1–2 mm in length that have been used in the aquarium hobby for decades as an invaluable live food for fish fry and small aquarium species. They are cultivated on a substrate of oatmeal, bread, or other carbohydrate-rich media and reproduce rapidly at room temperature, providing a continuous, self-sustaining supply of live food.

The starter kit contains an established 100ml culture with active microworms in their nutrient medium — ready to use immediately. By scooping a small amount of culture from the walls or surface of the container and rinsing it into the aquarium, thousands of wriggling microworms are delivered to waiting fry or small fish.

Microworms are particularly valuable because: they are tiny enough for very small fry mouths (1–3 day old fry of most species can eat them), they remain alive and wriggling in the water column for several hours, they sink slowly providing accessible food throughout the water column, and they are nutritionally rich in proteins and fatty acids essential for rapid fry growth.

Typical applications include feeding fry of livebearers (guppy, platy, molly, swordtail), egg-laying species (betta, tetras, corydoras, killifish), and small adult nano fish (Boraras, Microdevario, Endler's). Cultures self-perpetuate with regular feeding of dry oatmeal and can be maintained at room temperature indefinitely.

To maintain the microworm culture: keep the culture container at room temperature (20–25°C) with a loosely fitting lid to allow gas exchange. Feed every 3–5 days with a thin layer of dry instant oatmeal or bread crumbs spread on the surface of the culture medium. Culture will smell slightly yeasty — avoid strong ammonia odors which indicate overfeeding or contamination.

Harvest microworms by collecting them from the container walls and lid where they congregate. Rinse off the oatmeal medium into a cup of aquarium water and pour into the tank, or use a brush to collect directly from walls and swish in tank water.

Start a new culture every 3–4 weeks using a portion of the existing culture transferred to fresh oatmeal medium in a new container — this prevents cultures from crashing as they age. Maintain 2–3 cultures at different stages of development for continuous supply.

Store cultures away from direct sunlight and away from fruit flies — Drosophila flies will contaminate open cultures quickly. A loose lid allows gas exchange while reducing contamination risk.

Feed to fry 2–3 times daily in small amounts. Avoid overfeeding — excess microworms that sink and decompose can foul small fry tanks rapidly. Excellent supplemental food for adult nano fish including all Boraras species, Endler's, and other micro fish.