I want to add borax to my pool but my total alkalinity is high at 170 ppm. Can I add muratic acid to lower the total alkalinity which will also lower the pH and then add the borax to raise the pH back up to 7.4?
Welcome to TFP! The best way to increase pH without also increasing the TA you just lowered is with good/steady aeration. The instruction on the Lower Total Alkalinity - Trouble Free Pool page will help. Use MA to knock the pH down to about 7.0-7.2, then let the aeration increase the pH to about 7.8, perhaps even 8.0 before hitting it again with acid. You should see a biggest TA drop that way.