By Stephen Kwartler
First you must obtain a fresh starter culture of worms. I also suggest using several cultures in rotation so you will always have worms available. As soon as you receive your starter culture you should transfer them into a larger container. Tupperware type containers or plastic shoeboxes make good containers. The temperature should be between 65 to 75 degrees. Keep the container covered at all times to keep in moisture. Small holes must be put into the cover for air exchange. You can use many different cereal-based media for microworm cultures; including cooked breakfast cereals, moistened yellow cornmeal or wheat germ, and instant cereal products (i.e. Gerber Baby Oatmeal Cereal). We use yellow cornmeal as well as mixed baby cereal for culturing microworms successfully. To prepare a good long lasting formula, place medium (cereal) in a container to a depth of about one quarter to one half inch. Mix about one to two teaspoons of brewers yeast per culture in slightly warm water until the solution is quite milky. This water yeast solution should then be added to the cereal to the consistency of a thick shake. Add your starter culture of microworms and mix thoroughly with a plastic fork. Using a plastic fork is easier then using a spoon, as the medium will not cling to your fork, as it will when a spoon is used. In 3 to 5 days the worms will have covered the surface of the medium and will begin to climb up the sides of the container. At this stage they are easily collected with your finger or a wooden ice cream stick. We use an old toothbrush and dip the collected worms from the toothbrush into a small container of water. You can rinse the worms with the same net that is used for rinsing newly hatched baby brine shrimp. Feeding is done with the use of a baby eyedropper or a turkey baster.
It is important to stir your cultures after every feeding as it encourages reproduction and keeps the culture fresh. You may also find your cultures become soupy after only a few days of cultivating the worms. Adding additional cereal or cornmeal will keep your culture from becoming too loose or soupy. Remember to stir your cultures with a fork every time you feed them to your fish.
There are several additional benefits to culturing microworms. Besides having a supply of inexpensive live foods always available, you can also add liquid vitamins or other supplements to the culture. Remember whatever you feed your worms will be past on to your fish. Try to avoid letting the culture go bad, as it will give of a strong offensive beer like odor. Always wash your fork and the worm-collecting tool with each use to avoid bugs.
It is a good idea to begin a second container after a week. Begin a new culture by adding two or three spoonfuls from a good culture and mixing into a newly prepared container with yeast and cereal. When the first culture begins to turn it is time to dispose of that culture and begin using the newer one. We maintain between ten to fifteen cultures at all time to feed most of our juveniles.
For more information on culturing live fish foods, refer to the Encyclopedia of Live Foods by Charles Masters (1975,TFH).