In recent years the use of barley straw has become an increasingly popular way to improve water quality in ponds and water features. This technique, however, is actually a tried and true technique that has been used in Europe and other parts of the world for many years. When properly applied, naturally occurring organisms decompose the lignins in the barley, releasing humic substances (dissolved organic carbon) into the water. In the presence of sunlight and oxygen, those compounds are converted into low levels of hydrogen peroxide. The hydrogen peroxide is the component that modifies the pond chemistry to ensure water quality.
Barley straw typically provides results for three to four months. Apply second treatment three to four weeks before first treatment is done to ensure no interruption in control.
One pound per 75 square feet of surface area