2021/7/27/ · 2. Use of Fermentation Grooves. Steps: Build some grooves with at least three walls where you can place cow manure. The manure’s height can be 0,8m, 1.2m, or 1.5m. Keep turning the manure and leave it to compost. Screen your compost for contaminants like plastics. 3. Use of Fermentation Tanks.