Of the spa and pool water to make it perfectly. It acts by eliminating body fats and odors, removing impurities due to dissolved metals and, thanks to an energetic "flocculating" action, making water filtration much more effective. Kristal Blue is a natural based product that exerts an action clarifying of the spa and pool water to make it perfectly transparent And crystalline. The particular natural-based active ingredient it acts by eliminating body fats and odors, removing impurities due to dissolved metals and, thanks to an energetic "flocculating" action, making water filtration much more effective.