With activated barley. Designed to restore balance to the pond ecosystem by breaking down organic material that creates problems. Will work quickly & efficiently to clean the pond by reducing sludge in the pond & filtration devices. Reduces cloudy water by precipitating organic and inorganic materials. 100% natural and safe for all pond fish and plants! 2.5# treats 20,000 gallons 1# treats 8,000 gallons. Size: 1 lb.