at the risk of sounding silly, which clarifying shampoos? If you have hard water, and they contain a form of soap, castille or whatever, you're not clarifying, you're making it worse. Soap bars will make it worse. Anything with a soap type product. You need to use something with a chemical surfactant rather than a soap. Most "natural" shampoos are made out of liquid soap.
However, if its a detergent and its got citric acid in it, then I don't know what else to tell you. Sorry