Our fill water is high alkalinity, so I'm constantly fighting high PH due to drift. Due to a long illness with my mother in law last year, I wasn't able to keep on top of the the PH and it ran pretty high for the majority of the season. I now have calcium scale on a large portion of the liner.
When I closed the pool last year I adjusted the PH to 7.0 but the alk was still 150+. I had hoped the lowish PH would bring the calcium back into solution, and I think it did as it's not quite as bad as before, but it's still there.
I googled and found some older posts by Ben that talk of Sand algae and it seems like his recommendation was to lower PH to 6.8 and let it rise on it's own. I now have my alk at 80 ppm, so I'm hesitant in taking it that low as I have no idea how doing so will affect alk and what to expect.
When lowering Alk I drop PH right before a good rain, as I've found rain to be the best aerator going. When I've dropped PH and it doesn't rain like expected, it only takes a week at most for the PH to climb back up with no change in Alk. But that was at higher Alk levels.
Is this the answer? I assume I'd just use muriatic acid as before, but noticed that stain and scale products also lower PH quite a bit but have no idea if they'd be a better choice in this situation. Any help is greatly appreciated.