We have well water and it causes a lot of buildup in my hair. It tends to turn my blonde hair this golden, brassy color. My stylist recommended the Malibu C Crystal Gel to help remove buildup and brighten my highlights. I was amazed at the difference in my color. You could see the buildup coming out when my hair was rinsed. As a result, my highlights look nearly brand new vs. the old, brassy look. I love this product and look forward to using the Malibu Blondes Wellness System at home!