White Worms (Enchytraeus albidus) are are very easy to raise when kept in the right conditions and make an excellent live food source for a variety of carnivorous tropical fish species.
White worms are relatives of the common earthworm. They are white, seldom grow over 1″ in length, are free of parasites, are high in fat content, and hate light so much that they will die when kept under direct light.
Optimal conditions for raising white worms are:
- Cool temperatures
- The correct amount of moisture
- Darkness
Generally, white worms reproduce best when temperatures are kept below 70 degrees F. When temperatures exceed 80 degrees F., the worms will start dying out.
White Worms need food, a cool dark location, and a moist (not wet) substrate to thrive and reproduce. A dark corner on the floor of your basement would be an ideal location to raise your cultures.
Many tropical fish keeping enthusiasts use plastic containers to raise white worms, however, plastic containers can make it difficult to maintain the growing medium at the correct moisture level.
If the growing medium mixture is initially too wet when placed into a plastic container, it will remain wet and kill your white worm culture. Plastic containers will seal in the moisture. On the other hand, too little moisture can dry out the worms.
The culture medium should be just moist enough for you to form a ball in your hand that will not drip when squeezed.
Some tropical fish keeping enthusiasts prefer making small wood “worm boxes” from scraps of 1 X 4 pine boards. The wood helps to regulate the moisture content of the medium by absorbing any excess moisture and releasing it back into the medium if it begins to dry out.
Two or three small 6” X 6″ X 15” long boxes with a wood, Plexiglas, or glass cover will keep any tropical fish keeping enthusiast supplied with plenty of white worms.
Although mediums for growing white worms vary, potting soil or a 50/50 mixture of peat moss and potting soil are the most popular choices.
Place a 3″ or 4″ layer in a container of your choice, wet the medium with a bottle sprayer, mix thoroughly with a wood paint stirrer, and let it sit overnight.
Remix the medium the next day and lightly pat it down into the container before adding your starter worm culture.
White worm starter cultures can be purchased online, from breeders, aquarium clubs, fish forums, etc.
White worms are not picky eaters. They will eat almost anything but Cheerios, bread scraps, dry dog food, dry cat food, etc. are most often chosen as a food.
Place the worms at one end of the container and add a small amount of food just under the surface at the other end. Do NOT overfeed.
Check the container ever other day and if more food is needed, add a bit more. If food is still in the container after a few days, cut back on the amount you feed them.
All the food should disappear in 3 to 4 days.
When you start a new white worm culture, put a small amount of food in only one location. As the culture grows, gradually increase the amount of food and spread it out to the edges of the container. The worms will migrate to the food source.
In about a month, remove a small section of culture media along with the worms to start a second culture.
The white worms will form balls around the food and can easily be removed from the original culture with a plastic fork or spoon. Scoop up the worms along with some of the media from the original culture and bury them at one end of the second container.
It usually takes about 1 month to grow a good population of white worms in the original container to feed to your fish.
Use tweezers to pick out the white worms from the media or scoop out a mass and place them in a container of water. They will ball up in the water and can be easily removed free of any growing medium.
You can also place a plastic container lid on the surface of the medium. The worms will congregate on the underside of the plastic lid and can be scraped off as needed to feed your fish.
Over time, the culture medium will begin to “sour”, but if you manage several containers and periodically add fresh medium to the original batch as you remove the worms and older medium, the original batch will stay refreshed.
Because it takes such a long time to get a new culture of white worms going, it’s much better to replace the medium a little bit at a time and keep several cultures on hand than to start a fresh new culture every time a batch goes “sour”. Mark the dates on each container to keep track of everything.
When raising white worms, a long, narrow, relatively shallow container is preferable to a round, deep container. This is mainly because of the migrating tendencies of white worms.
When using a long container, you can “heard” the white worms to one end of the container by placing the food at one end only. When the worms migrate to the food, the old medium at the other end of the container can be easily scooped out and replaced without disturbing the entire culture.
This is not possible when a round container is used.
Remember that white worms are high in fat content and should not be exclusively fed to most fish species.
Unless your fish are being conditioned for breeding, most tropical fish keeping enthusiasts recommend feeding white worms no more than three times a week.
Unlike live tubifex, black worms, and other aquatic worms, white worms are free from parasites and are undoubtedly one of the best conditioning foods you can provide to your fish.