Live food culturing

How to culture Microworms (Panagrellus redivivus)

Supplies needed

Microworm starter culture
Plastic container with lid (16-32oz)
Instant oats (rolled or quick)
Active dry yeast
Water
Toothpick or popsicle stick

Step-by-step

Step 1: Mix culture mediumIn container: mix 1 cup instant oats with enough water to make a thick paste (oatmeal consistency). Add 1/4 teaspoon active dry yeast. Stir.

Step 2: InoculateDrop a portion of the starter culture onto the medium. Spread evenly. Don't mix in - microworms migrate to surface.

Step 3: Cover looselyPunch 4-6 small holes in the lid for ventilation. NOT airtight - microworms need oxygen.

Step 4: Wait 7-10 daysWorms multiply on the surface + climb the container walls when culture matures.

Step 5: Harvest from wallsWipe walls with a toothpick or finger. Microworms accumulate as a paste. Mix with a few drops of water; offer to fry via dropper.

Step 6: Rotate culturesEach culture lasts 2-3 weeks. Start a new culture every week from existing one. Always have 2-3 active cultures.

FAQ

How long do microworms live?

Individual microworms 30 days. Cultures last 2-3 weeks before going sour (smelly + unproductive). Always rotate fresh cultures.

Are microworms or vinegar eels better for fry?

Microworms are slightly larger (1-2mm) and more nutritious. Vinegar eels are tinier (0.5-1mm) and last longer in water. Use both.

Can adult fish eat microworms?

Yes - any fish that takes flake will eat microworms. Treat for adults, staple for fry.

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Aquarium-keeping fundamentals

Whatever specific topic brought you here, four fundamentals govern long-term aquarium success: water quality, parameter stability, biological filtration, and species-appropriate husbandry. Skip any one and the others struggle to compensate.

Water quality: ammonia + nitrite at zero, nitrate under 30 ppm freshwater + 10 ppm reef. Test weekly with API or Salifert kits. Use our water parameter checker to score your readings against your tank type.

Parameter stability: stable wrong parameters beat fluctuating ideal parameters. Most fish tolerate a wide pH range if it's stable. Sudden swings of 0.4+ pH or 5+°F kill fish faster than chronic suboptimal values. Use temperature controllers (Inkbird) + automated dosing for consistency.

Biological filtration: the bacterial colony on your filter media + rock + substrate is the engine. Never replace all media at once. Use our filter turnover calculator to size correctly.

Species-appropriate husbandry: research adult size, territoriality, diet, and tankmate compatibility before purchase. Use our tank stocking calculator + compatibility guides.

Frequently asked questions

How long does an aquarium take to set up? 4-6 weeks for full cycling + first stocking. Use our cycle ETA calculator + how long does cycling take.

What's the best aquarium for beginners? 20-gallon long. Big enough for parameter stability, small enough for budget + space. See beginner picks.

How often should I do water changes? 25-30% weekly. See water change frequency Q&A + water change calculator.

Why does my fish keep dying? 5 leading causes: uncycled tank, wrong species pairings, no quarantine, undersized tank, neglected water-change schedule. See full diagnosis.