Redworm



Eisenia fetida (older spelling: foetida), known under various common names such as redworm, brandling worm, tiger worm and red wiggler worm, red californian earth worm, is a species of earthworm adapted to decaying organic material. These worms thrive in rotting vegetation, compost, and manure; they are epigeal. They are rarely found in soil, instead preferring conditions that are inimical to some other worms.

Eisenia fetida worms are used for vermicomposting. They are native to Europe, but have been introduced (both intentionally and unintentionally) to every other continent except Antarctica, occasionally threatening native species.

Eisenia fetida is closely related to Eisenia andrei, also referred to as E. foetida andrei. The only simple way of distinguishing the two species is that E. foetida is lighter in colour. Molecular analyses have confirmed their identity as separate species and breeding experiments have shown that they do not produce hybrids.

Reproduction
As with other earthworm species, Eisenia fetida is hermaphroditic. However, two worms are still required for reproduction. The two worms join clitellums, the large orangeish bands which contain the worms' reproductive organs, and which are only visible during the reproduction process. The two worms exchange sperm. Both worms then secrete cocoons which contain several eggs each. These cocoons are lemon-shaped and are pale yellow at first, becoming more brownish as the worms inside become mature. These cocoons are clearly visible to the naked eye.

Use in Aquaponics
Gererally, Redworms are widely sold by weight for use in vermiculture owing to their remarkable ability to process organic matter into fertile compost. They are also sold as bait and can be used as fish feed

Redworms can further decompose the residue of a Black Soldier Fly colony and produce fertile compost. See BSFL and redworms

Redworms and/or other earthworms can also be put into ex-clay- or gravel-filled growbeds to reduce organic solids buildup. They also feed on biofilms with important nitrifying bacteria, but these regenerate quickly in a well-balanced system.

As the worms reproduce under above conditions, some of the worms can be harvested regularly and fed to the fish.