A tank measuring 10’ x 6’ x 3’ is made of brick – with holes in the side walls to ensure adequate supply of air during composting. The brick tank is filled with farm wastes, soil and cow dung and water is added to maintain moisture between 60– 75%. A tank is filled with soil (16–18 qtls), farm wastes (14–16 qtls) and cow dung (1–1.2 qtls). Water is added to moisten the material and the upper layer is plastered with the soil and dung mixture. Tank should have protective roofing from direct sun and rain.

After 75–90 days of composting, a microbial culture of azotobacter, rhizobium and phosphate solubilizing bacteria is added to the mixture.  Compost becomes ready for use within 110–120 days. One tank provides about 2.5–2.7 tonnes of compost sufficient for one hectare of land.