Here is an draft extract from my soon to be published killifish website. Hope it is of some help to you.
Whiteworm (Enchytraeus Albidus) are another form of livefood I like to give to my adult Killifish, but they are more difficult to culture successfully than Microworm or Grindalworm.
Old aquarists swore by wooden boxes as a recepticle to culture these worms in. I, myself have found that plastic biscuit boxes are ideal. The medium I use for propagating these worms is not my own recipe but one I've tried as a result of conferring with other aquarists over the years. It's basically a 50/50 mix of potting compost and peat moss. I boil the peat first then I mix the two soils together and form a large damp ball then... wait for it....I microwave the ball for around 2 minutes. (Don't tell the wife, I do this when she's at work). My secrets out... Anyway I believe this has the affect of sterilising the soil and there will be no nasty living organisms to infest my whiteworm culture. Fill the container to a depth of around 75mm. As to feeding the worms I personally use brown bread soaked in milk. Change the bread if it becomes mouldy, but you will soon get used to feeding the right amount so as the worms consume the whole lot. You will probably be saying to yourself, well I use a different food and get better results. I've tried different foods and found that this works well for me. Again cover the whole culture with a piece of glass. Puncture the lid with random holes for air to circulate. Now the most important part of cultivating Whiteworm is the temperature of which you will store your cultures. Whiteworm are most productive stored at a temperature range between 55 - 65 degrees Fahrenheit. Anything over this temperature they become unproductive and begin to die. So Temperature is the most critical criteria to successfully cultivating Whiteworm.
