High PH and Low TA

fjdavid

Member
Jul 28, 2008
7
Indianapolis, Indiana
I have been having some slight issues with the PH. I started with the BBB method this year and I use the Taylor test kit. Here is where I'm at from last night.

PH 7.8
FC 4.0
CC 0.0
TA 80
CH 210
CYA 40

The PH seems to keep rising slowly (not bouncing) so when I add Muriatic acid the PH drops and the TA drops. Lately the PH seem to rise over a week from 7.4 to 7.8. I thought it was the rain we had in June (over 9") but its been dry in July and still doing it. We are not using the pool a lot and the kids are older so they tend to just float to tan instead of splashing around. There is a 1/2 tube with water flowing into the pool over the edge of the pool from my small solar heater I built from irigation tubing, but not much splashing.

What can I do to get the PH lower but the TA to stay at 80 or raise it towards 100.
 

Bama Rambler

Mod Squad
TFP Expert
Bronze Supporter
LifeTime Supporter
Jun 22, 2009
23,626
SouthWest Alabama
Honestly why do you want the TA at 80 or 100 if your pH keeps rising. Let it go to 70 or so and see what happens to the pH. It might settle down and not rise at all and if it does it'll probably be a lot slower.

If you're convinced on raising it you can overshoot the pH lowering a tiny bit then use use Baking soda to ring the TA back up afterwards.
 

mnb

Well-known member
Feb 18, 2009
75
NW Chicago Suburb, IL
Does your ph continue to rise above 7.8 if you do nothing?

The reason I ask is this. Last year and at the beginning of this year I was always trying to keep my ph around 7.5 or so. It would go up to 7.7-7.8 and I would hit it with acid to bring it down. Constantly repeating the process.

So I decided to not adjust the ph and see if it would continue to rise. It went to 7.8 and has been there for weeks now. No adjusting by me. Even with tons of swimming and the slide being on. I guess my pool just wants to be at 7.8. I'm fine with it as I no longer have to add acid.

Might be worth just seeing if it will stop at 7.8 for your pool.
 

fjdavid

Member
Jul 28, 2008
7
Indianapolis, Indiana
It has been at 7.8 for the past two days. I'll let it go for a while longer to see if it continues upward. The reason I was concerned about the TA was it started at 100 and has dropped to 80 when I tried to get the PH to stay at 7.4 I was concerned that it would continue to drop below 80. The suggested TA for my pool is 80-100 I thought. I'll wait and see what happens over the week and post the results.
 

benavidescj

LifeTime Supporter
Apr 27, 2010
431
Fleming Island, FL
TA recommendation of 80-100 is just that, a recommendation. If you water chemistry is happier at slightly lower values then so be it. Mine sits a 70 and does not move too much. My pH rises constantly (mostly because I have a SWG and my plaster is still curing).
 

duraleigh

Admin
Mod Squad
TFP Expert
Platinum Supporter
LifeTime Supporter
In The Industry
Apr 1, 2007
32,852
Sebring, Florida
fjdavid,

All good advice above. If you decide to raise your TA and keep your pH almost constant, use baking soda per the pool calculator.
 

chem geek

TFP Expert
LifeTime Supporter
Mar 28, 2007
12,083
San Rafael, CA USA
You can let the TA get quite a bit lower than 80 ppm without a problem, though 50 ppm would probably be a lower limit just to have some pH buffering in the water. Since your pool is vinyl, you won't need to raise the CH to compensate to keep the saturation index near zero as you would need to do with a plaster pool. This chart shows how much over-carbonation is in your pool and you can see that as the pH gets higher or the TA gets lower things are far less out-of-balance.
 

fjdavid

Member
Jul 28, 2008
7
Indianapolis, Indiana
I've been watching the PH for the past two weeks and if I do nothing it went up to 8.0 so I added acid to bring it back down to 7.2 and let the PH rise on its own. That was on the 20th. last night the PH was back up to 7.8 so it takes about 10 days to go from 7.2 to 7.8. At first I thought it was from all of the rain in June but July has been very dry in central Indiana. I guess its nothing to worry about but I don't understand what is making it continue rise so much. There's not a lot of splashing going on since the kids are older and not using the pool much lately. Anyway thanks for the info. I'll just keep an eye on it.
 

NewHomeowner

Well-known member
Jul 16, 2014
98
Westport, CT
Hi all. I have similar high PH and low TA issues upon just opening the pool for the season.
My results are a bit wacky and as follows:

PH 8.2+ (9 per pool store, rich magenta color beyond scale of my Taylor test)
TC 0 (although I just added 5 gallons of 12.5% bleach to bring to shock level)
TA 60 (70 per pool store)
CH 175 (140 per pool store)
CYA 25

I'm not certain which to do first as I have no idea what my real PH is. The pool store suggests bringing my alkalinity up first, and then add acid, and finally calcium hardness.
I will use baking soda, muriatic acid, and BJs ice melt (99% calcium chloride) instead of the pool store products.

Any thoughts?
 

epro05

Bronze Supporter
Jun 5, 2014
279
Keller, Texas
I am happy at a TA of 60 and a pH of 7.8. With my other values, CSI is close to 0.0, which also makes my happy. My pH rises more slowly now than when my TA was 80. If my pH rises to 8.0 I only add a few oz of MA to bring it back to 7.8. That seems to be my pools "happy point".