As a starter, for those who may be concerned, the worms look like human pinworms, but cannot successfully infect a human due to the low temperature requirements of this worm, and to the best of my knowledge, do not carry an pathogens as can be gotten with tubifex worms.
First, you need a place that can hold a temperature below 70 degrees F. Second you need a starter culture. (The culture comes second since at above 70 degrees Fahrenheit your worms won’t do well at all. A temperature between 55 and 65 is best if you expect them to reproduce. I prefer to use a Styrofoam box, like a fish box (with lid), since the box will help stabilize the temperature, and the lid maintain darkness which they demand or hide. An unheated integral garage, an old basement refrigerator set to as high as you can without turning it off, or some other “cold” spot in the house works well. I have heard schemes for raising white worms at above 70 degrees using sponges and water evaporation to keep them cool, but never tried it.
For a medium, I find that Magic Worm Bedding, available at Wal-Mart in the hunting and fishing supplies department is great. They even have a small worm box with bedding for under $10 if you do not need a large culture. I prefer to use a Fish shipping box usually available at your local fish shop, sometimes free, sometimes for a dollar.
When you obtain a starter culture, you will find it is not a lot of worms. A one pound starter culture from a commercial supplier (priced usually around $15) is a pound of dirt, not a pound of worms. It will be several weeks if not months to raise enough worms to feed unless your fish room has a single male guppy and planted tanks only. Once established the supply is reasonable and can be raided for food once or twice a week for a treat for your fish. Many say that the white worms are a high starch food and should be fed sparingly and certainly not as a mainstay; however I have never seen a problem with fish fed exclusively on white worms although I would not recommend it.
The worm bedding is very dry (weight minimized for shipping) and must be soaked in dechlorinated tap water prior to use. You can put some water right in the box (which has a yellow bag inside that holds the bedding). The bedding looks like it may have a little sand and some peat moss or other mulm, but is much better for raising the worms than a sack of topsoil or other readily available medium. Unless you plan to supply the eastern seaboard with worms, the cost of the Magic Worm Bedding is minimal.
Squeeze all the water you can from the bedding to make it just moist. Fill your box with about 3 to 5 inches deep with the bedding and “fluff” it up a little. Excess water will eventually go to the bottom so if it is a little wet it will not hurt.
Place your starter culture right on top of the bedding. There are many foods that ca be used for the worms. Some prefer Pabulum or mashed potatoes placed in small furrows in the medium, but I prefer to use a piece of bread soaked in non fat dry milk. Some bread is less prone to mold and I like the “Italiano” brand sliced bread since it will hold for several days soaked in milk prior to any mold development.
For a starter culture, half a slice is plenty. When the remaining bread shows signs of mold, remove and replace it with a fresh slice. Once established, a good culture will consume a slice of bread in about 36 to 48 hours.
Now here is the nice part about using bread as a food for the worms. Once established, the worms will consume, and actually replace the bread slice. This means you do not have any “separation” task, just scoop up a clump of worms, and place them in water to rinse away any bread remnants, replace the cloudy water with fresh water, and baste them into the tanks. This is a good culture 12 hours after placing a new slice of bread into the box.
Unlike black worms, white worms cannot survive under water indefinitely, so you will need to remove uneaten worms the next day if you used more than could be consumed.
After a few months, the worm bedding may become fouled. You can tell this by seeing if the worms are “trying to exit the box by climbing up the sides. When this happens, start a second box culture by splitting the culture into a second box and adding a fresh batch of worm bedding to each box.