Natural Chemistry Spa Alkalinity Increaser boosts your spa or hot tubs alkalinity level into the optimal range, which is an important factor for keeping your spa balanced. A balanced alkalinity level also prevents corrosion damage to plumbing, equipment, and spa surfaces as well as bather irritation. Its all-natural formula stabilizes your pH to make your sanitizer much more effective and simplify maintenance by eliminating "pH bounce." Spa Alkalinity Increaser will make chemically balancing your spa or hot tub much easier and headache-free.