Living in the Hamptons, we mostly have well water here, hard water, not good for a blonde or anyone with lighter hair! Not only does it dull and weigh hair down, the hard water and my copper pipes cause my locks to turn a blue-green color! Malibu C Hard Water treatment is a must-have! I use it every other shampoo even though I have a shower filter for hard water. My hair is actually silky again with Malibu C, oh and no blue-green hue! I also brighten up my blonde with the Malibu Blondes treatment...love it!