Nature Sheen is a highly concentrated formulation that quickly and effectively clears hot tub water. You use very litte to achieve a lot, unlike other general clarifiers that require large dosages to be effective. Over time, water naturally loses its sparkle as it accumulates waste particulate that is too small to filter out. Nature Sheen works through agglomeration, pulling tiny particulate into masses large enough to be filtered out. Most effective when applied each week, on a maintenance basis.