Question about lowering TA and strange Ph readings

May 19, 2012
7
Temecula, CA
Hi there
I have a plaster pool that was redone in early 2019 and everything has been OK with it. I just "reopened" meaning fully cleaned my DE filter, vacuumed all the Crud and started prepping for summer swimming.

When I started, the first thing I did was get work on the CYA knowing it was an issue. When all my refills arrived for the TF-100 kit, I took measurements.

FC 0
PH 8.2
TA 200
CA 260
CYA 40-50

I knew I needed to get my TA down and have managed to get it to 130 now. I expected the Ph to go down considerably and while it was briefly down, its back up to 8.2 as of today.

FC 3.0
CC 0.5
PH 8.2
TA 130
CA 260
CYA 40-50

My pool is in full sun and gets windy in the afternoon. I'm wondering if the movement on the top of the water would be enough to bring the Ph back up or am I missing something? Even after I added a gallon of muriatic acid this last time, the TA did not go down and as mentioned the Ph went from 7.4 back up to 8.2 in course of a couple of weeks.

I feel like there is some organic staining on the plaster too - brushing gets the pollen off but this bit stays behind. With reading on here, I can only assume its staining but I guess could be algae? Its down low in the deep end (8ft deep end) along the sides where it kind of rolls to the bottom.

I want to do a shock series but was hoping to get the other numbers in a good place - do you think I should just shock instead of worrying about getting Ph and TA balanced?
Not sure where to go from here.

Any ideas? Thanks in advance
Anne

Temecula, CA
 

Richard320

TFP Expert
LifeTime Supporter
Jan 6, 2010
23,858
San Dimas, CA (LA County)
You wrote, "Ph went from 7.4 back up to 8.2 in course of a couple of weeks."

That's normal. Actually, exceptional. My TA is much lower but my pH still climbs regularly. Any fill water you added will add to the pH and TA as well. For me, every time I add 2" of water I have to add a quart of acid. YMMV. Hot windy weather means twice a week.

Just check and adjust pH a couple times a week until TA settles down (if it ever does)

Now the next item. We don't advocate for anyone "to do a shock series." We do the SLAM Process that follows a certain set of rules and ends with three tests, one of which is Overnight Chlorine Loss Test If you think you have algae, either kill it all or don't bother.
 
May 19, 2012
7
Temecula, CA
Ooh, thanks. My bad for the terminology. I haven't been on the site in awhile as I have been doing OK with the balancing. :) I will read up on the Overnight Chlorine Loss test.

As for the Ph, yes, I have to add fill water every 3 days or so. I will keep working on the Ph. Appreciate your response.