Common names for the Eisenia foetida are: Redworm, Red Wiggler, Tiger Worm, Manure Worm, Fish Worm, Striped Worm, Composting Redworm, as well as many other names. Worms are annelids, a word derived from Latin meaning "rings." The Redworm (Eisenia foetida) is an Epigeic worm. Epigeic worms live on the surface of the soil or in the top 10 inches or so of the topsoil under the litter layer. Redworms are the workhorses of the composting world and tend to be smaller than Anecic worms, or "earthworms," which build and live in deeper more permanent burrows. Nightcrawlers are Anecic worms and are much bigger than redworms. Redworms can eat about 3 times their weight a week. Redworms reduce the volume of that waste by about two thirds. They mature in 8 weeks and double in biomass every 3-4 months under ideal conditions. That means that if you start with one pound of worms, in three to four months you will have 2 pounds of redworms. In eight months you will have four to five pounds of redworms, etc. 1 mature worm could produce 96 worms in 6 months (2 cocoons X 24 weeks X 2 hatchlings).

Redworms are not nightcrawlers. Redworms behavior, reproduction rates, and size are very different from nightcrawlers. Redworms stay where they are happy and fed, nightcrawlers tend to crawl at night when there is no light to keep them contained. Redworms reproduce very fast, nightcrawlers are very slow to reproduce. The size of redworms vary from a length of 35 to 130mm (generally less than 70mm) or 1 1/2 inches to 5 inches; their diameter is 3-5mm or 1/16th to 1/8th inch.