Grindal Worms
An easy culture to grow and great for feeding young fish with small mouths.

Starter culture purchased from The Bug Farm. They have reasonable prices and are very customer service oriented. They frequently list live food supplies at Aquabid.com. Seller alias, Thebugfarm.

The Bug Farm sends complete instructions on how to raise all of their cultures.

How I keep my supply of Grindal worms:

For me, I use plastic containers (14" x 10" x 8" deep).
I have had a lot of luck with this culture using only Peat Moss.
Place the peat moss in a bucket and saturate with water. You may need to knead the peat moss until it absorbs the water. Wring out (squeeze out excess water) peat moss and place into container. Make media about 4 inches deep. (From here, I microwave media for about 5 minutes on High to kill any organisms that might be in the peat moss. Allow peat moss to cool to room temperature).
Using a finger tip, dig a small trench in center of media about 1/2 inch deep and add new culture.
Lightly cover new culture with peat moss.
FEED the new culture with single grain oatmeal baby cereal.

How to feed:
Sprinkle baby food right above new culture (sprinkle like you were using salt the "healthy way"). Using a mister, mist cereal until completely wet...that is the cereal being wet, not the peat moss.
Do not feed again until all cereal is gone.
Gradually spread baby cereal further out each feeding...meaning cover more area other than the initial feeding. This will make your culture move out from original placement. Eventually, you will be covering the entire surface area of your container.
If you should get a fungus growing in your media, scoop out fungus and allow the very top of the area where fungus was growing to dry out a bit DO NOT ALLOW ALL MEDIA TO COMPLETELY DRY OUT, this will kill your culture. Fungus on peat moss can be caused by the following:

• Not enough air circulation
  
• Over watering
  
• Too much baby cereal added for consumption
  

Harvesting your culture:
The Grindal worms will collect on top of the media during feedings. When your culture is mature you can easily scrape them off with a pair of tweezers.

I scrape them off the top of the media the day after a feeding of baby cereal (this way I don't have to worry about getting cereal in the fish tanks) and then swish them in a glass of water. The worms seem to clump while any media sinks to the bottom of the glass. I can then use a pipette to remove the worms for feeding.

For tanks with no bed/gravel, I don't have to worry about collecting worms with the peat moss or media added, as this will sink to the bottom and I can easily siphon it out later (next day) as it collects on the bottom of the tank.

BTW...these worms do not seem to be sensitive to chlorine/chloramine in water.