Have been using Silk Balance for a little over 1 year now since purchase of our Tub. It is an EXCELLENT product. Have been in many spas and the water is silky smooth. Many friends have commented on the fact their skin is not as dry as when they come out of other tubs. Another benefit is the fact that it balances the Ph and Alkalinity. In the entire 14 months we have owned the tub I have only had to adjust Ph and Alkalinity on 2 occasions. The water is always balanced. Highly recommend this product.