Does it warrant investigation? Well, sure, and it has been....thousands and thousands of times over with posts on TFP detailing just how wrong pool stores get it. So, if you look at the data in aggregate, not just specific instances, it is much more likely that the pool store is wrong than you are.
Understood and agreed. I never rely on pool store tests, only use them on occasion to bounds-check my own results due my color perception issues. If something of concern comes of it, where else to go to clarify than here?
I usually ignore the results, but this *particular* case was odd enough to make me raise an eyebrow and ask the question, just in case I was off on my tests. While certainly within the realm of coincidence, it would have been much easier to ignore if they were wildly off in different directions. ?
To be clear that I'm being clear, I'm not saying I trust their tests. I'm simply saying I question my own at times and this is the only way I have to get additional data points to check mine against. No good can come of pool stores, I know.
With an SWG it is doubly important to track CSI as the chemistry inside the cell tends to be different than bulk pool water. For TFP recommended levels, plaster pools and pools with SWG's tend to run at lower TA to avoid the pH rise that you seem to be experiencing. Since TA has a big effect on CSI, one needs to balance the lower TA against another variable to keep the CSI from dropping into a corrosive zone. Adding a little extra CH to the water helps to allow TFP users to maintain a lower TA and still keep a balance water saturation.
Ah, THAT answers my question. It hadn't occurred to me that we run a lower TA range with SWG, so balancing it with higher CH now makes sense.
With my TA around 70, as long as my CSI is staying within range there's no need to increase my CH, correct?
For the pH issue, I have considered borates, and I may revisit. I don't mind adding a bit more acid if I have to add it less often. Last time I brought it up the response was not overwhelmingly positive.
Based on my test results, can you see any other factors for my pH rise? I don't run my aerator, I have no waterfalls or features, the pool runs at night, and the return jets are positioned to just move the surface of the water but never break it. I don't have a large bio-load. The pool is honestly barely used. No kids, only occasional use by the 2 of us, so extremely low bather load. Leaves and other debris are cleaned out as often/quickly as possible and never left to sit in skimmers, etc., to break down. Fill water is softened and the pH is around 7.7. No sprinklers or other runoff. I think I've done as much preventative steps as I can to keep pH in check, yet it still climbs fast.
