Barley straw can be used to reduce the amount of algae and blanket weed growing in the pond. As the straw decays, allelopathic compounds are released and the microbial activity takes up free nutrients in the pond. For best results remove as much as possible of the algae before introducing the barley straw, which typically takes about 4-6 weeks to become effective and lasts about three to six months. The amount supplied is appropriate for ponds up to 2000 gallons (9000 litres). You may be skeptical but as a natural remedy you have little to lose by trying it!
