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Wow, Just tested for TA 120. pH 7.2 This poses an interesting question. I'm at the very high end for TA and at the very low end for pH
I believe this is a common newbie mistake. You mention that you are are at the very end of the ranges for PH and alkalinity. My advice, quit while your ahead. You have both in range. Now look at what those reading do in the long run after use and adding sanitizers. I like to take a minimalist approach to adding chemicals and get things in range and don't try for perfection.