Microworm culture with worms climbing side of plastic container

How To Culture Live Microworms Without A Starter

To culture live microworms without a starter follow these steps:

  1. Hollow out two halves of potato
  2. Bury the 2 hollow halves of potato in the ground
  3. Wait 1 to 2 week to allow microworms to colonise the buried potato
  4. Carefully dig up the 2 potato halves you buried. Scrape the inside of the potato, these scrapings are your starter!
  5. Prepare some quick oats or oatmeal
  6. Add the oatmeal to the plastic container
  7. Sprinkle yeast on top of the oatmeal
  8. Add your potato scrapings which contain microworms from step 4 or starter culture
  9. Cut air holes in the contain lid and store the culture at room temperature
  10. After 3 to 5 days your microworm culture should be thriving!

See below for more information on microworms and details on each step to starting your own live microworm culture.

What are Microworms (Panagrellus Redivivus)?

Microworms (Panagrellus redivivus) are small usually 1 to 3mm long,white worms that move almost constantly. Due to their size and shape, they can be successfully fed to fish that are too small to take baby brine shrimp.

Why Should You Culture Live Microworms?

Live foods are critical for successfully raising fish fry especially in the first few weeks.

Microworms are a great live food to feed your fish and fry. The small size of Microworms makes them a very suitable live food source for fry particularly for very small fry who can not yet eat baby brine shrimp.

Microworms are also nutritious consisting of 76% water and 24% protein and fat.

Live Microworm cultures are easy and inexpensive to keep and provide an additional food source for you fish and fry, so the benefits seem to outweigh any negatives.

Microworms is the water column during feeding
Microworms is the water column during feeding

How To Culture Live Microworms Without A Starter

Things you will need:

If you have a starter culture and you want to start a second culture jump straight to step 5.

To start a live microworm culture without a starter you first need to get some mircoworms ie create your own starter.

  1. Hollow out two halves of potato

    Take a potato and cut it in half. For each half dig out the middle of the potato. You should end up with two halves of potato which have been hollowed out.

  2. Bury the 2 hollow halves of potato in the ground

    They should be buried about 10cm (4 inches) deep, and the soil should be moist. Bury the potato halves with the cut side of the potato face down and the skin side face up.

  3. Wait 1 to 2 week to allow microworms to colonise the buried potato.

  4. Carefully dig up the 2 potato halves you buried

    Scrape the inside of the potato, these scrapings are your starter!

  5. Prepare some quick oats or oatmeal

    Take a bowl and add some quick oats or oatmeal there needs to be enough to cover the bottom of your plastic take away food container you plan to use.

    Then add hot water and allow the oats to absorb the water. The mixture should have a very thick paste-like consistency, moist yet keep some shape. There should not be any excess water remaining.

  6. Oatmeal mixture for Microworm culture
    Oatmeal mixture for Microworm culture
  7. Add the oatmeal to the plastic container

    Once the oatmeal has cooled scoop it into your plastic food container. The oatmeal should cover the bottom of the plastic container and be between 1 and 2 centimetres deep.

  8. Sprinkle yeast on top of the oatmeal

    Lightly sprinkle some dry yeast over the top of the soaked oatmeal. The exact amount is not crucial. The yeast serves as additional food for the microworms.

    The Microworms feed on the yeast and bacteria produced from the oatmeal.

  9. Add your potato scrapings which contain microworms from step 4 or starter culture.

    Spread your starting microworms on top of the oatmeal base.

  10. Cut air holes in the contain lid and store the culture at room temperature

    Your Microworms needs air so you will need to put holes in the lid of you plastic container.

    Two popular options are to drill or poke small holes in the lid or cut a larger hole and then fill it with cotton wool or filter floss.

    There should not be any large gaps or holes where flies or other insects can get in and spoil the culture.

    The culture should be kept in a well-lit area at room temperature, between 20 - 29°C (68 - 85°F).

  11. Lid for Microworm culture with air holes cut and cotton wool in place to prevent bugs entering
    Lid for Microworm culture with air holes cut and cotton wool in place to prevent bugs entering
  12. After 3 to 5 days your microworm culture should be thriving!

    After 3 to 5 days you should notice the surface of your microworm culture shimmering or wriggling, these are the microworms wriggling about!

Once you have a successful microworm culture you can use that culture as a starter for another culture. Simply use 1 spoon of worms from your existing culture as the starter and follow steps 5 to 10 above.

Harvesting Microworms

Once the microworms have populated and covered the oatmeal they will start to crawl up the side of the plastic container.

The microworms can be harvest by wiping your finger along the side of the plastic container to pick up the microworms, alternatively you can use a Q-tip.

To feed your fry or fish you then simply dip your finger or Q-tip into the aquarium. The mircoworms will then be suspended in the water and you fish will start to feast on them!

Microworm culture with worms climbing side of plastic container
Microworm culture with worms climbing side of plastic container

Tips To Maintain Microworm Cultures

You should gently stir your microworm culture once a week to keep them thriving. Unlike other worms microworms do not bury.

It is good practice to always have 2 cultures of microworms at a time. This ensures that if a culture crashes or fails you still have a backup and will always have microworms available to feed you fish and fry. Plus you will always be able to start a new culture.

Write the date that you start the culture on the lid. This way you know how old the culture is and when you need to think about starting a new culture.

Microworm cultures have a vinegar smell to them this in normal.

Microworm cultures usually last 4 to 5 weeks but this can vary based on the environment they are kept in. Warmer temperatures increase their metabolism rate meaning they multiply quicker and generally the cultures expire sooner.

Overtime as the yeast utilizes the oatmeal the culture will become runnier and soup like. When it begins to get runny but is still with thriving microworms make a new culture.

As more time passes the culture will become increasingly soup like and start to smell bad and possibly grow mold, at this point the culture should be discarded.

Frequently asked Questions (FAQ)

How long does a Microworm culture last?

Microworm cultures typically last 4 to 6 weeks.

What do Microworms eat?

The microworms feed on the yeast and bacteria produced from the oatmeal.