About a year ago the third chlorine generator I've installed in my pool bit the dust. The pool was built in 2008. After reading how high Ph levels can shorten the life of chlorine generators I decided to really get serious about keeping it in check. I had been relying on my local pool store for water analysis, but of course this was a weekly, not a daily ritual, and virtually every time I had it checked my pH levels would be high. Saltwater pools are notorious for high pH levels. The generation of chlorine is the culprit. Keeping the pH between 7.4 and 7.6 with 7.2 being the minimum means you're going to be adding acid every 2 to 3 days at least. Buy it by the case. So I purchase the best test kit available, the Taylor K-2006C and became almost obsessive about checking not only my pH levels but also the total alkalinity. it's a delicate dance keeping your pH and alkalinity levels in their proper ranges. Adding your acid VERY slowly in front of your most powerful jet will have the least effect on your total alkalinity. Over the years a significant white calcium line had developed all around the siding. I tried pretty much every suggestion I could find for removing this line but nothing had much if any effect. I basically just gave up and excepted it as a fact of owning a pool. But guess what, it's not. Over the past year that I've been diligent about my pH and alkalinity levels the line has almost disappeared. I wish I had a before picture so you could see just how bad it was. The second picture shows what's left in some areas, but I'm sure given where it's come from that this too will disappear. Hopefully posting this in this forum will help new pool owners avoid this problem altogether.