Fermented Barley Straw Extract. Barley straw has been used for hundreds of years to promote clean clear water conditions in ponds and streams. EcoBarley Liquid Extract is a pharmaceutical grade fermented barley straw extract that has been concentrated to give you a clean clear pond. The added enzymes will help reduce pond maintenance by breaking down pond sludge and keeping filter pads cleaner. Provides clear clean pond conditions. Starts working instantly. Concentrated formulation with added enzymes. 1 Bottle treats up to 20 000 gal./75 684 liters. 1 Pump treats up to 100 gal./378 liters. Size: 1liter/33.8oz.