Maintaining a compost bin and worms

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In this section we will only mention the levels compost bin model, probably the most appropriate for domestic or small scale composting, but many other models exist.

The bin

The compost is a levels model. In this model (see above left), when a level is full, another level can be added, and the worms migrate to fresh food. It currently consists of two stacked tanks (see above right), but may be extended by similar containers (see above center). The lower tray (4), used to recover the liquid compost tea, is covered with a plastic bag to improve its seal. The top and center trays (2) serves to house the worms and compost waste. They have holes at the bottom, allowing the liquid to flow. At the sides holes are pierced for air and covered with a cloth to prevent insects from entering. Covering the bottom container, a plastic bag with holes (3) prevents worms from falling into the liquid. The top level of the bin is closed with a cover.
When the top tray is full, a new floor can be added (see above center). Just find the same size of polystyrene box (10kg) for the upper floor: Drill the bottom holes of 0.5 cm every few inches, drill vents on the side and close them with cloth. Then you can stack the new floor and put fresh food inside.

Regular maintenance

The regular bin maintenance is to monitor the content, e.g. weekly, and correct the system if it is going wrong. Open the bin and prospect the contents to identify:
§ Presence of Compost tea.
§ Smell, compost color and moist level in the bin
§ Living populations and their global spatial distribution, proportion and evolution
o Adult worms and if they try to escape the bin
o Babies and young worms, signs of well being
o Microorganisms, e.g. Mold, Acarids, Collembola, Flyes (see nextsection).
Young worms are the best indicator of the good quality of the content of the bin. If everything goes well, they can be found everywhere. Young worms or cocoons resemble to white threads or brown balls of few millimeters. When things go wrong, the worms stop reproducing, and if it's going very bad, they will try to massively leave the bin, for example by taking refuge in the lower tray. Un bébé vers sort du cocon[[#_ftn3|[3]]]