I added 26oz of Borax last week, the Ph rose from 7.4 to 8.2. I added 8 oz of Ph Minus (1.75 lbs per 10,000), and it is still testing 8.2 two days later. I bought new Ph reagent, thinking this is 2 yrs old now, maybe not accurate, but the new test gives the same results. I bought a new container of "Slo Lo" from the pool store and added 6oz last night. The water still tests 8.2. This is the OTO simple test, verified by my aquarium chem set.
So my best guess is my Ph must have gone much higher than I thought, and the initial 8.2 was just the highest the test read. I am thinking dilute a sample by 50% and retest. Any chemical experts have an alternate suggestion?