I have owned a Bullfrog Spa for about five years. During that time I have experimented with all kinds of chemicals with not a lot of success. Two years ago I purchased my first bottle of Silk Balance and will never use anything but Silk Balance. If you keep up on your PH level, one treatment a week and your water is clear and clean. I have recommended this to all my friends who have spas. Thanks Bullfrog Spas for recommending it to me.