Guanokalong Black Pellets organic base nutrient Guano black is a mixture of Guanokalong powder and humic acids in soft pelletized form. Use Guano black as a base fertilizer to mix with your soil or soil/Coco based medium. The humus is made from 100% leonardite (highly oxidized lignite). It conditions the soil. It stimulates micro-life. It creates high levels of permanent humus. It reduces re-planting stress and water demand. It has a high PH and water buffering capacity.