Crystal Blue Copper Sulfate Smart Crystals Moss & Algae Killer, 5 lb. effectively controls most types of algae, making it an i solution for maintaining clear and healthy water environments. This product can be applied in several ways: by casting copper crystals directly over floating algae mats, dissolving them in water to spray, or placing the crystals in a porous bag to drag behind a boat. To ensure safety and prevent oxygen depletion, it is to treat a portion of the pond at a time. The crystals come in a convenient ready-to-use 5 lb. pour container, designed to cover an area of 1 acre with a water depth of 1 foot. This makes it easy to manage algae growth efficiently and effectively. Model Number: