City water straight from the faucet was 6.7-6.8 as we filled the pool. I not sure why municipal water would be so acidic, but pool math says 83oz of dry borax for 7.3ph with 6500 gallons. i checked the ph this morning and it still is 6.8. How soon can the kids get in after I put the borax in? I started with 24oz of chlorine last night at ten pm and let the filter/skimmer all in one run all night last night. Thanks. my kit for pool testing is on its way...I used my ph test kit from API for aquariums. city water, 6.8, pool 6.8, aquarium 7.4! btw