By Bill Malay Reprint from THE AQUARIAN
Here's a proven method of culturing Infusoria for raising the fry of
your egg layers. With this method, a one-gallon culture will support
about one hundred young fish until they are past the Infusoria stage.
There are ways to raise the fry of egg layers that require infusoria as
their first food. One of the main reasons most of the newly hatched fish
disappear is that, when Infusoria is fed, there is too much of the
contaminated water in the tank, thus killing the fry.
The materials needed are at least two test tubes, a one gallon wide
mouth jar, a quart jar to stand the tubes upright in after they are
filled with Infusoria water, a syringe bulb with rigid plastic tubing
inserted in the open end of the bulb, and some lettuce leaves. The water
used is taken out of a tank that has aged water and fish in it. The
method used is as follows:
Fill the one gallon jar with the water from the tank, and add 1/2 dozen
lettuce leaves. In about 3 days, you will notice a scum forming in the
jar. Next, take the syringe and suck the water and scum from the top of
the jar, not going in deeper than 1/4". Now take a handkerchief, or
bleached muslin, such as an old sheet, and strain the water taken from
the jar of Infusoria through the handkerchief into a small jar or cup.
This removes most of the scum particles.
Fill the two test tubes with the strained water and stand them upright
in the jar over night. The next morning you will notice that the
Infusoria has risen to the top of the test tubes. Pour only about 1/2
inch of this into a tank that has fry in it and pour the rest back into
the Infusoria jar.
Do not put an airstone into the gallon jar as this would keep them
swirling in the jar and they would not collect in the top in a mass as
you want them to. My theory is that the reason the Infusoria collect in
the cultured jar, and also in the test tubes, is that they come up for
This amount of Infusoria culture that you have in the jar will smell
foul, but that does not harm your fish as you harvest almost pure
Infusoria each morning and night until the fry are ready for Microworms
or other food. A 1 gallon culture will support about 100 young fish
until they are past the Infusoria stage.
Keep looking at the bellies of the fry to make sure that they are full
at all times. A magnifying glass is very helpful in checking the young
fry and also to see how much Infusoria is already in the tank with them.