1 pack treats up to 250 square feet of water Aquascape Lake Sludge Remover Packs eliminate organic sludge or muck from lakes and large ponds, enhancing water clarity and quality while removing odors. The easy-to-use water-soluble packs dose the sludge layer directly and make it easy to spot-treat or treat hard-to-reach areas. This treatment works great on lake bottoms, beach areas, and shorelines. The packs contain all active ingredients with no harmful fillers or binders and an added carbon source aids in proper denitrification. Lake Sludge Remover Packs slowly release oxygen to maximize sludge reduction and include added macrobiotics to effectively reduce sludge between doses. This treatment is for lake and large pond use only and may cause issues in smaller enclosed systems. Safe for fish, plants, and animals when used as directed.