Microworm Starter Culture

About this culture

Microworms are tiny nematodes cultured on a simple oats or porridge medium. They are one of the easiest first live foods for newly free-swimming fry — small enough for tiny mouths, nutritious, and they crawl up the sides of the tub for effortless harvesting. A single starter keeps producing for weeks, and starting a fresh tub every 2–3 weeks keeps the line going indefinitely.

Best for

• Betta & gourami fry
• Tetra, danio & rainbowfish fry
• Corydoras fry
• Any fry too small for baby brine shrimp

How to culture it

1. Mix plain oats or instant porridge with water to a thick paste, ±1 cm deep in a shallow tub with a ventilated lid.
2. Spread the starter over the surface. Keep at room temperature, out of direct sun.
3. Worms are climbing the walls and ready to harvest in about 3–7 days.
4. Start a new tub every 2–3 weeks before the old one sours. Keep two tubs running so you never run out mid-spawn.

How to feed it

Wipe worms off the wall with a wet finger, cotton bud or brush, swirl in a little tank water and pipette into the fry tank.

Microworms sink and survive a short while in water — feed little and often, close to the fry.

Go deeper: How to culture microworms & banana worms →