How to Make Infusoria for Baby Fish

Updated on December 28, 2016
An infusoria culture.
An infusoria culture.


Liquifry is a product that feeds the infusoria in the tank and promoted the growth of the small organisms that fry feed on. Many breeders swear by liquifry, although buyers should be aware that it is not so much fish food as it is food for the fish food.

When raising small fish fry, the first challenge you'll run into is the one that involves feeding invisible food to invisible fish. The first kind of food young fry of small fish species need is infusoria. 'Infusoria'
is a term that refers to microscopic life forms such as protozoa that live in fish tanks, though not usually in large enough numbers to sustain a few hundred hungry baby fry.

Infusoria are essential for small fry such as betta fry and guppy fry, as new free swimming fry are simply unable to feed on other live foods. Even baby brine shrimp and micro worms may be too large for small fry. A good supply of infusoria will help your fry through the first vital days of their lives and make sure that their stomachs are always full.

So, as a responsible breeder, you will need to culture infusoria for your fish fry. You should do this 3-4 days before you expect the fry to hatch as it takes 3-4 days for the culture to really take off.

For starters you'll need some tank water. Its good if you have an established tank that likely already has significant numbers of microscopic lifeforms living in it. Add to the tank water some organic food, such as cut grass, a rabbit pellet, or blended lettuce.

Make sure that the culture has easy access to oxygen, and place the jar in a sunny spot. Over the next three to four days you should see the water go cloudy and then clear once more. You will want to wait until the water has cleared, as this is the sign of a successful and 'clean' culture. Once you have clear water, add a little to your tank to feed your fry.

How you do this depends largely on your personal preference and what works for you. Some people recommend a slow siphon method that supplies a constant stream of fresh infusoria into the tank. Others recommend simply tipping half the culture into the tank. This is slightly more risky. It's important in either case to ensure that the organic matter does not end up in the tank. Then you'll simply have rotting organic matter in your fry tank, which can cause all sorts of problems. 

Be aware that it is potentially possible to introduce nasties to your tank by carelessly making infusoria. Bacteria and some non friendly biological organisms such as dragon fly larvae can be a problem, however I have found that, if properly managed, the risk of problems is far outweighed by baby fish which have fed well in the first few days of their lives. Stunted fry are frustrating and demoralizing to raise and may never do as well as their better fed counterparts.


    0 of 8192 characters used
    Post Comment

    • profile image

      britaney 4 years ago

      You may want to keep it open for the oxygen to get into the jar

    • profile image

      Jay 6 years ago

      Do we need to close the jar or cover it with nail holes sheet? please advice...

    • profile image

      fishguy 6 years ago

      probably from the grass

    • profile image

      vidar 6 years ago

      How do dragonfly larvae get in?