Hello all... new to forum and this is my first post.
I have read all that I can find regarding adding borate to a pool and am considering adding to my pool, but would like an answer to some questions first. I have an ~15,500 gallon pool (about 5 months old) with a SWG. My CYA is at 40, TA is at 90, FC is at 4 and stable, CH is at 260, and my salt is at 3600 according to the generator, but the test strips say it's 2800. I am finding that my pH is at 8.0 about every three days and the acid demand test tends to take 1 drop indicating I need a pint of acid according to the Pool Calculator, which is correct because pH is at 7.6 the next day. If I wait 5-6 days it takes two drops and a few ounces shy of a quart to get the pH to 7.6. Now I understand that the SWG is the likely culprit for the rising pH plus some aeration from spa overflow.
So, my question is... will adding borate to 40 ppm quantitatively extend the time required before pH rises out of range? If yes, has anyone actually observed the difference? How many days before and after for comparison? If yes, does this increased time actually offset acid use over the same defined time period? I ask the last question because I see the presence of the borate will require much more acid to effect the same reduction in pH due to it's buffering ability. According to the Pool Calculator it would take 16 oz to go from 8.0 to 7.6 without any borate in the pool and 49 oz with borate at 40ppm. That's triple the amount of acid! In the end, are you really saving any acid (aka money) or are just adding more acid far less frequently and consuming the same amount. In my situation, I'll add 48 oz over nine days, or 16 oz every three days. Will borate just make that roughly 49 oz every nine days or even longer?
If borate maintains desired pH for a sufficiently longer time period than no borate, then that's less testing and less frequent addition of acid, which is a good thing in my book.
I eagerly await responses.
Free form plaster pool and spa with three overflows
(Jandy) Stealth Pro 2-speed pump, DEV DE filter, JXi Heater, AquaPure SWG