I have a 20' x 40', in-ground, vinyl liner pool with Pentair Equipment including a Salt Chlorine generator and heater. The pool is in north Alabama. The pool was installed and operational by the first of August 2023, but the salt cell was not online until we opened the pool in March 2024. The pool was covered over the late fall/winter with pump running all winter. My variable speed pump runs 24/7, with my SCG chlorine generation set at 23%. I have been tweaking that percentage to best keep my chlorine levels steady.
When I opened the pool in March, the water was clear, with chlorine level at 5 ppm, leftover from use of chlorine pucks prior to covering pool in November. The pH and TA were relatively low 7.0 pH and 60+ TA. I targeted pH to be around 100-110 and got the pH to be around 7.4. HOWEVER, soon after, I have seen a rollercoaster of rise in PH followed by me applying dry acid to lower the pH. The problem is that i can lower pH to 7.3 to 7.5 but it leaps back up to 8.0 in a matter of 2-4 days, and this is a "rinse and repeat" story. I have now lowered my pH so often that I have burned down my TA to 65-80 depending on whether you believe one pool company or another, or my digital tests.
My Chlorine has always run in the 1 - 3.5 ppm range
My TA has always run in the 80-110 ppm range
My Total Hardness has run in the 210 - 250 range
My pH seems to "want to be around 7.9 to 8.2", as if that is its' balance and in fact using LSI (my water seems to need higher pH to be "Saturation index balanced".
But, I react to pH at or above 8 by making efforts to bring it down to 7.4/7.5, .............but it just bounces right back.
My CYA levels began with levels that came from the chlorine pucks used last summer, so the levels have reduced from the 60's to the 40's to low 50's
Present chemistry:
Total Chlorine - 2.4
Free Chlorine - 2.27
Combined Cl - 0.13
Total Alkalinity - 80
pH - 8.0
CYA - 42
Total Hardness - 214
NOTE: I have NEVER had cloudy water. The water is beautiful, but my amateur mind says, "keep pH between 7.2 and 7.8, with ideal level at 7.4-7.6, but i cannot keep pH steady.
NOTE: All of my reporting has been through period between March 8 and May 10, with very little pool usage by 1-2 adults, when daytime temps and pool heating allowed for use.
I have read online that Borates added to pool might help further buffer pH bounce, but haven't used them.
Finally, Saturation Index formulas and calculations seem to be wildly inconsistent when I compute it manually with Pentair documentation, or use Orenda App or other Apps for LSI or CSI (is there a difference?). I bring this up because if I trust the LSI formula in Orenda App, i have balanced pool water when I have high pH levels, as if pool wants to be there to be balanced. It is counter to the literature that says keep your pH down in 7.2 - 7.6 or other near ranges.
So, all of the above is to say that with my vinyl liner pool and use of salt chlorine generator, i am frustrated by my pH being impossible to control, given the chemistry levels I have the pool set at. Because i have administered so much dry acid over the past 3-4 weeks, i have driven my TA down. I also know that lower TA allows me to use less "pH reducer" product to get the pH down. But does it also make it much easier to bounce back?
Finally, I am thinking that i could really lower my pH temporarily, then jack up my TA to 100 to 110, then add Borates to resist the bounce. If that theory is unfounded, I am at my wits end for finding ways to keep pH relatively steady. I just don't think I should be having to put acid in pool every 3-4 days.
When I opened the pool in March, the water was clear, with chlorine level at 5 ppm, leftover from use of chlorine pucks prior to covering pool in November. The pH and TA were relatively low 7.0 pH and 60+ TA. I targeted pH to be around 100-110 and got the pH to be around 7.4. HOWEVER, soon after, I have seen a rollercoaster of rise in PH followed by me applying dry acid to lower the pH. The problem is that i can lower pH to 7.3 to 7.5 but it leaps back up to 8.0 in a matter of 2-4 days, and this is a "rinse and repeat" story. I have now lowered my pH so often that I have burned down my TA to 65-80 depending on whether you believe one pool company or another, or my digital tests.
My Chlorine has always run in the 1 - 3.5 ppm range
My TA has always run in the 80-110 ppm range
My Total Hardness has run in the 210 - 250 range
My pH seems to "want to be around 7.9 to 8.2", as if that is its' balance and in fact using LSI (my water seems to need higher pH to be "Saturation index balanced".
But, I react to pH at or above 8 by making efforts to bring it down to 7.4/7.5, .............but it just bounces right back.
My CYA levels began with levels that came from the chlorine pucks used last summer, so the levels have reduced from the 60's to the 40's to low 50's
Present chemistry:
Total Chlorine - 2.4
Free Chlorine - 2.27
Combined Cl - 0.13
Total Alkalinity - 80
pH - 8.0
CYA - 42
Total Hardness - 214
NOTE: I have NEVER had cloudy water. The water is beautiful, but my amateur mind says, "keep pH between 7.2 and 7.8, with ideal level at 7.4-7.6, but i cannot keep pH steady.
NOTE: All of my reporting has been through period between March 8 and May 10, with very little pool usage by 1-2 adults, when daytime temps and pool heating allowed for use.
I have read online that Borates added to pool might help further buffer pH bounce, but haven't used them.
Finally, Saturation Index formulas and calculations seem to be wildly inconsistent when I compute it manually with Pentair documentation, or use Orenda App or other Apps for LSI or CSI (is there a difference?). I bring this up because if I trust the LSI formula in Orenda App, i have balanced pool water when I have high pH levels, as if pool wants to be there to be balanced. It is counter to the literature that says keep your pH down in 7.2 - 7.6 or other near ranges.
So, all of the above is to say that with my vinyl liner pool and use of salt chlorine generator, i am frustrated by my pH being impossible to control, given the chemistry levels I have the pool set at. Because i have administered so much dry acid over the past 3-4 weeks, i have driven my TA down. I also know that lower TA allows me to use less "pH reducer" product to get the pH down. But does it also make it much easier to bounce back?
Finally, I am thinking that i could really lower my pH temporarily, then jack up my TA to 100 to 110, then add Borates to resist the bounce. If that theory is unfounded, I am at my wits end for finding ways to keep pH relatively steady. I just don't think I should be having to put acid in pool every 3-4 days.
