u/Icy-Swimming-530

I’m 43 days into flower. I have a pH problem I’ve realized after using a soil meter instead of the test strips. It’s at 5.5 pH and the leaves have been gradually turning this way for weeks. I went on vacation for a week and had someone check on them, watering once and when I returned it looked like this but before wasn’t so uniformly brown.

So they look like this because of pH and lack of watering. Idk how to fix my pH quickly and my tap water is off the charts high. Can I flush with something at the store? I wish there was just a one stop fix all solution for this ph thing.

I use dechlorinator, ph down, organic powdered nutrients, and all these change the ph and with test strips I can only test once.