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A full set of accurate water test results from a TF-100 or Taylor K-2006C test kit would be most helpful, but those products can impact chemistry a bit. They do little for scale and staining can usually be addressed independently based on the type of stain (organic, iron, copper). I wouldn't add anymore. Instead, if you don't have a proper test kit yet, use that $$ for that very purpose and post a full set of test results. That will be much more helpful for all of us.
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