A few questions about my water

[grrltraveler]

Hi all and thanks in advance for any help on this one

I got on here awhile back when we moved our pool equipment and subsequently had to shock the pool etc. Living in such a dry and sunny environment, I was having to add chlorine and tweak the ph often, as well I was cleaning the pool a lot and we weren't using it (April, May, June). My DH can't swim and my DD is in her first yr learning without floaties and goes to another pool EVERY day so I covered up the pool with the solar cover and, lo and behold, things started maintaining better. I didn't have to add so much chlorine (if any) every day, the pH was maintaining better, I didn't have to add so much water since it wasn't evaporating as much and the pool was cleaner. I continue to run the pump daily and the polaris once or twice a week. Then it started getting REALLY hot here and we took the cover off at the weekend to swim. The temperature (with no heater) is like bath water (my thermometer says 90 but i don't know). I am just telling you this in case it makes a difference. Since the beginning of July, I noticed that each time I did the test, the pH was up to 7.5 and I brought it back down to 7.2. Chlorine didn't change much unless the cover was off for a while or we were swimming. Water is sparkling by the way.

So I did a full test this morning and
FC 5.0 (I had been keeping at 6 because my CYA was 50-55 a few weeks ago)
CC 0.0 (hadn't changed from last night, when I measured it after swimming)
pH 7.5
TA 80
CYA 30 (this was the first time I'd done the test as someone recently suggested, outside, look away for a minute and back, pour back into bottle and do 3 times to get more accurate so maybe it was wrong before)
CH didn't check but we know its 550 or so

So now that my CYA may officially be 30 and not 50, is this an OK number or should I be moving it up a bit to keep my pH more stable etc?
Is there any reason the CYA would drop (I think I raised it when we were shocking the pool 4-5 months ago) - is it unusual for it to drop?

I have everything on hand to get started (just need to find the socks!) but was hoping I could find out if there was more I needed to do.

Thanks so much and happy Sunday!!
Anne

 

[JasonLion]

Nothing you described sounds surprising or unusual or to require any special action on your part.

If you are mostly keeping the pool covered, having CYA at 30 is fine. If you are going to leave it uncovered for several weeks, then it is worth raising the CYA level.

It is easier to maintain the PH if you keep PH between 7.5 and 7.8, instead of below 7.5. I suppose you are keeping the PH lower because of the high CH level, which is a reasonable thing to do. But it will be easier if you lower TA a bit, which will also allow you to let PH go up a little higher.

Using a cover saves chlorine.

CYA tends to drift down over time, not usually quite that quickly, but that isn't surprising. You lose CYA to splash out and backwashing the filter.

 

[grrltraveler]

Thanks Jason, yes, I'm keeping the pH lower (some long term person on here recommended) due to high CH. I will go check out what I need to do to lower the TA a bit. I guess I don't need to panic as much as I thought.

Thanks so much