Nature's Blue S.C., 1 Quart Nature's Blue is formulated to give your pond a long lasting natural blue color. One quart of super concentrate (S. C.) will treat one surface acre of water 4' to 6'. Nature's Blue should be added as needed. It is important to never let the blue fade for this will give weeds and algae a chance to become established making them difficult to control. In colder climates Nature's Blue should be added just before winter to stop sunlight from penetrating the ice. No water use restrictions and is safe for humans, fish and other wildlife. Note: One Quart of S.C. is equivalent to regular strength gallons on the market!