Still having PH issues..

MCF50

Well-known member
Aug 18, 2020
254
Houston
Plaster saltwater pool is about 9 months old. U can see my numbers below. In an attempt to cool water a bit a run bubblers 2 hours in the middle of the night. I also generate chlorine in three 2 hour intervals during the night. Then I run the pump (no chlorine) at a higher speed for an hour during day to help skimmers. My PH is bumping up .1 to .2 per day. I would like to drop alkalinity to 50 and allow ph to float around 7.4. But when the ph and alkalinity are this low CSI goes too negative. A pH of 7.8 bothers my eyes which is why I prefer 7.2. At this point I am strongly considering the Pentair Intellichem system to dose the muriatic acid as I am tired of adding 3-6oz every 3-4 days to keep Ph below 7.8. And when it gets to 7.8 it rises to 8.0 and above as fast as it when from 7.4 to 7.6. It never seems to hit a high level and stabilize. If it would sit at 7.8 I would learn to live with it but it doesn’t. It just keeps climbing even though alkalinity is at 70. Thoughts ideas something I have not thought of??
 

MCF50

Well-known member
Aug 18, 2020
254
Houston
I never mentioned baking soda. I never add it. Checking the ph this morning after 12 hours it went from 7.2 to 7.4. This was with swcg running 6 hours over night, bubblers running for 2 of those six, and a very gently overflow from hot tub to pool (wide opening, water runs down wall from hot tub to pool). Any additional thoughts?
 

vanelli56

New member
Jun 20, 2021
2
South Carolina
Pool Size
14500
Surface
Vinyl
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-40
I am a total newbie... but, I thought I read that bubbler, overflows, spillways, etc... they all add surface turbulence which can cause your Ph to rise. Perhaps turning off the bubblers except when wanted while in the pool?
 
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zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
13,802
Houston, Texas
I would try lowering the TA to 60 first and see how that works for you. Another factor that may help is that next week is supposed to give us a break from the near daily torrential rain storms we've had lately. I don't know what part of town your in but where I am we've had at least one 30 minute long pounding thunderstorm every day. Prolonged hard rains aerate the pool and drive pH up. Aussietta was referring to your Poolmath logs that showed additions of baking soda, however the last entry was over 5 months ago, so if you have not added baking soda since then I doubt it is part of the issue now. I would stop running the bubblers at night. They probably don't help much to cool the pool. The best cooling occurs with fine mist of water shot high in the air allowing the heat to evaporate out, however this will also drive up pH. Anything that churns the surface of the water aerates the pool and drives up pH.

You can certainly try automation to add doses of MA to your pool, as to which system will work best I can't say. You have several factors working together to drive up pH that may resolve by next summer. By next summer your plaster will be over a year old, and we probably won't have daily deluges all summer. The SWG also drives up pH but if the additional factors resolve the rise should be slower.

This Saturday there will be a live discussion on pH and TA by some of our TFP experts. Featured - TFP Expert Discussion - pH and Alkalinity You can either watch live or watch the recorded version of the conversation after it is posted on our YouTube channel. It may have some helpful information for you.
 
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MCF50

Well-known member
Aug 18, 2020
254
Houston
Thank you so much!!!! I thought I updated my log with all my chemistry levels yesterday. My bad! Right now the only thing I add is muriatic acid on a regular basis. I am in Houston so the rains are horrible. I also add Calcium Hardness Increaser (to keep it around 450), stabilizer (keep it around 80-90), and salt (keep it around 3200ppm) when the rains lower everything.

I will lower the Ph to 60 as recommended. I will also turn off the bubblers at night.

Does running the pumps during the day or night really make any difference? The returns do not churn the surface of the water. Like I said I do have a gentle spillover from hot tub to pool when pump is running.

Levels as of last night
TA 70
Ph 7.2 (was up to 7.4 this morning)
CH - 400
Salt - 3200ppm
Stabilizer - 90ppm
FC - 6ppm
 

zea3

Mod Squad
TFP Expert
LifeTime Supporter
Jul 10, 2009
13,802
Houston, Texas
It won't make a difference for pool chemistry if you run the pump day or night. If you are on one of those electricity plans where evenings are free it may be less expensive to run the pump at night. As far as pH rise, rain contributes, new plaster contributes, SWG contributes, churning water contributes. Except for the SWG those are all things that can be changed or in the case of new plaster, changes over time.

Your CH is good between 250 and 450, so you don't need to immediately bump it back up. Houston area water is fairly hard, so when we have a dryer summer you probably won't need to add calcium. You can run a CH test on your tap water if you want to know how hard it is.

If you are interested in cooling the pool, search for diy pool coolers in the search bar and you should get a few threads showing how to build one.
 

MCF50

Well-known member
Aug 18, 2020
254
Houston
Thank you! Well as water temps seem ok for now and the bubblers haven't really been doing anything to cool as you stated, I will hold off on adding anything that can increase PH until things settle down.