Microworms are small nematode worms that grow to be around 0.5-1.5 mm in length. They are a great food source for fish fry, especially fry that are too big for infusoria and too small for brine shrimp. Microworms are easy to grow at home and definitely recommended if you want to breed fish species that produce tiny fry.

  1. Get 2-3 suitable containers. This way, you will always have a constant supply of microworms. Plastic 2 liter ice-cream containers with tight fitting lids will work great.
  2. Obtain a starter culture from your local fish store or aquarium club.
  3. Provide your microworms with some type of food. Different growers use different recipes, but microworms aren’t that fuzzy when it comes too food. Try to find a food source that is convenient to use for you and do not be afraid to experiment. One example of a food combination that have proven useful for other microworm growers are 1 cup of quick oats + 1 ¼ cup of cup of warm water.
  4. Pour food into the container and leave it to cool. If the mix is too warm, it can kill the microworms.
  5. Add your starter culture to the box, put the lid on and leave the box in a fairly cool place. The temperature will affect the growth rate of microworms: they grow fast in warm temperatures and slow in cooler ones. You can therefore experiment until you find a growth rate that is ideal for your needs. In a comparatively cool place, the worms will start coming out of the food mix and crawl the sides of the box after a few weeks.
  6. When you can see microworms crawl the sides of the box, simply remove them and add them to your aquarium. Using worms from the sides of the box is less messy and you can avoid getting any mixture into your aquarium.
  7. Stir the food mix once in while, since this is known to increase the growth rate.

After a few more weeks (depending on temperature), the food mix will have deteriorated and can give off a foul smell. It will also look darker than before. Use worms from this box to start a new culture in the second box. When the second box has become well established, you can clean out the first box. If you need even more food, start a third culture after roughly three weeks.