Last year I came upon a discovery through the help of experts on here, that has helped me mange pool care much easier and faster and cheaper. I later found that I was not alone, and there have been some other members come to this same realization due to the characteristics of our pools that makes us have to manage it slightly out of range on one of the levels. This has been a real work and product saver, and it's taken me from a TFP subscriber that did not have a trouble-free pool to one who does. What was happening, not being very chemically oriented in my head, and therefore not having a full understanding of the "whys", I was just simply taking all the recommended levels as the bible on pool care, I was trying to keep all my levels in check and adjusting as religiously as I could to keep all the levels in the recommended ranges. It was, however, anything but trouble free. With everything in balance, the PH would creep up out of range about every two days; I'd add the recommended acid and keep going. I got really good at knowing my pool and exactly how much to add to get the desired effect. About every two weeks, just as pool math would suggest, my TA would drop out of range due to the continual additions of acid. And then, being a good student, I would immediately bring the TA back between 70-90 with soda.
I finally took to the forum asking if it was okay to let my pool drift up and stay at or about 8.0-8.1, because it seemed to quit drifting beyond that point, and I had found that the originator of the BBB method on another site had written an article claiming higher PH was okay for pools that sort of equalized at that higher level. What I didn't know at that time, because again, I'm not chemically minded, was that another parameter, the TA could be allowed to fall below the 70 level to solve this whole problem.
The remaining problem for me is that, even though I've read over all the CSI stuff and out gassing stuff relating to why some pools are different and need lower TA levels to stay in balance, I'm still having problems understanding all these numbers and how they work together.
I opened my pool and everything except for FC was in range; ph was on the low end of the range, but still in range. FC was a little high. In late Fall, when I closed the pool I shocked it and closed it as per TFP instructions. I don't know if maybe I over did it a little or what, but I expecting to have to shock the pool or at least add some bleach when I reopened, but in reality, I'm having to let the sun consume some chlorine before adding. Three days later, I've got something new I've not had since the pre-TFP days when I was using trichlor pucks w/o reservation, and that's low PH. Way low. I've checked in twice in two days, and it's at or near 6.8. Unlike in those pre-TFP days, this time around I've gone out and bought some borax. I added 34 oz by volume and will recheck today. It should put it up to 7.2. I'll recheck and add if necessary.
Pool Opening / 3 days later
FC 7 / 4.5
CC 0 0 / 0
CYA 31 * Did not retest but tested 3 times on day one and got a consistent reading just above the 30 line before the water clouded to the point
TA 50 50
CH 250 * Did not retest.
First question: I figured this would be a good time to go back through pool school to make sure I still know what I think I know about pool care. That's when I noticed the recommendation for TA has changed from 70-90, to 50-90 for vinyl pools. Does anyone know what brought about this change. I know that's much closer to making my pool work, as I had to let mine go down 40-45 to keep PH in balance.
Second question: Not being chemically minded, how is adding these borates going to effect this equation, as I've read they can add some buffering? Should I just sort of hang on until I get the PH in range and see what happens and maybe my new equalized TA will be a little different or something else?
Third question: What in the world would cause my PH to crash after opening. It dropped actually on day two from about 7.3 to 6.8 in one day. I've let the pump/filter run, after backwashing on low for the first 24 hours. I tested twice with the same result regarding the low PH. I didn't have anything to raise PH except for aerating, so I aerated a little and let it go. I tested again on day three with some borax on hand. It again measured 6.8. I added enough borax to raise to 7.2 as per pool math. Though I'd raise a little and recheck today.
Any advice is appreciated. This is a new phenomenon to me.
Thanks in advance to the experts on this site for what you do.