That was probably my comment, and it is an observation that I have made, for which I have no explanation
I have been around plaster for many years, and like the old saying "birds of a feather flock together", so have most of my friends. No matter where in the country (I even have a pool in Cabo that I am involved with, and it holds true there as well) they are, the Pebble pools always tend to have higher pH than plaster pools.
I have honestly never asked why (so thank you for asking!), and I might just learn something now!
Yes it was your comment Bruce. I have a pebble pool that has rising pH. I do have a SWG which obviously causes a lot of it, but when I saw your comment I was intrigued. Maybe someone has an explanation for it.
Pebble surfaces are less reactive than plaster surfaces and should react something like a pool that was 7/8 vinyl and 1/8 plaster.
I suspect it has to do with the kind of equipment purchased with a pebble pool, rather than anything inherent to the pebble surface. Pebble pool owners are more likely to purchase a SWG, more likely to have water features to cause aeration, etc just because they are spending more money.
Leaving the PH high gives you significantly higher risk for calcium scaling and metal stains, depending on your chemical levels in the water.
PH drift can be minimized by lowering TA to around 60, or better still adding borates to around 30 to 50 and then lowering TA to around 50.
I do not have a SWCG, but I do have a waterfall and a raised spa, so I know I aerate considerably (my pool runs 6 hours a day, and everything runs when it is on). I check pH daily, or every other day at the most, and I usually have to add 8-16 ounces a day to keep pH in check. I have not added borates yet, but it is something that I am considering.
Interesting. I'd like to see what percentage of Pebble pool owners have a SWCG and/or aeration compared to using liquid chlorine and no aeration. It would be interesting to see if the pH spike is still on the latter pools.
What's the best way to do a poll on the forum? I would like to see if it is in fact related to pebble owners owning a SWG. The poll should include non-pebble owners as well to see if there truly is a difference.