My test numbers today are: salt content 3400...free chlorine 11...PH level 8...Alkalinity 80...CYA...80...Calcium hardness 325...Pool Math recommends 18oz. of the muriatic acid. I am trying to keep the PH at 7.4 but this goal is hard to achieve. I am adding Muir acid every 3 days...Any suggestions
Is there a way to reduce the quantity of muriatic acid added
- Thread starter David Gentile
- Start date
- Jun 22, 2014
- 47,802
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
There is no need to try and force the pH that low. If your pH likes to hoover around 7.7-7.8, that's fine. In addition, you can allow the TA to fall a little bit more (~60) which should help to slow the rise of pH. Hope that helps.
Hello Pat... I know my numbers are good overall. The pool water is perfectly clear... Are you suggesting that I lower the alkalinity to 60 or 70 and that this will lower the PH?
- Jun 22, 2014
- 47,802
- Pool Size
- 17888
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-45 Plus
Not exactly. We lower the pH with acid, but in many pools, especially salt, the pH seems to like the upper 7 range. Along with that, it's often helpful to keep the TA a little lower (around 60 or so) because it does help to slow the increase of pH or its tendency to creep over 8.0. Our pools will always require acid to keep the pH in-check, but keeping the TA a little lower and minimizing any other forms of aeration should help reduce how often you have to add acid.
Hi Pat, I appreciate you taking the time to clarify your answer...I am running my pool pump 12 hour per day at 1600 rpm. I am going to lower the alkalinity into the 60 to 70 range...Thank you
Just be careful that you do not crash your pH while trying to lower TA. For example, using your 12k gal pool with 31.45% MA, 16 ozs will lower pH by 0.3 and lower TA by 5.2ppm So take it in stages. Add MA, let the pH rise a little after a few days then add more MA again. Lowering TA is a slower process than lowering pH.
I noticed you have a waterfall and spillover Spa. Whenever you have aeration your pH will tend to rise. Also since you have a saltwater system, there is extra pH generated from the salt being turned into chlorine. My pool had an infinity edge (no longer have this pool, hence had) and the pH rise was forever a battle to keep it in check. But once I added the Borates things stabilized dramatically. 70-80 was the sweet spot for my Alkalinity. Every pool is different, but I highly recommend you learn about adding Borates to your pool here on the forum. For me it was worth it.
So you want to add borates to your pool--Why and How
A few folks asked for a sticky on this so here it is. If you just want to jump to how without the why look for the blue part of this post below! :wink: Several companies are selling sodium tetraborate pentahydrate as a pool additive under such names as Proteam's Supreme, Bioguard's Optimizer...
www.troublefreepool.com
Here is where you find the information regarding Borates.
I can tell you what I have found in my pool. I gradually dropped my TA to around 40 ppm and that stopped the incessant rise of pH; like you I was marveling at my pools appetite for MA. Considering Borates is a possible solution to buffering pH rise, too. I, personally, think you are correct in pushing your pH into the 7.2-7.4 range as it makes your chlorine a much more effective sanitizer. Chlorine is 33% effective at 7.8 pH and 66% effective at 7.2 pH. (And at the price of chlorine these days...) I shoot for 7.2, though no lower. That gives me effective sanitation at 3.0 ppm chlorine.
Considering the "red eyes" common rhetoric, the normal pH range for tears has been tested at a pH of 6.5 to 7.6; the mean value being 7.0 pH, so I don't think an accurately measured 7.2 pH is a problem. I've never had any complaints, but if you received some you could always edge up a point or two.
CDC Fact Sheet
Considering the "red eyes" common rhetoric, the normal pH range for tears has been tested at a pH of 6.5 to 7.6; the mean value being 7.0 pH, so I don't think an accurately measured 7.2 pH is a problem. I've never had any complaints, but if you received some you could always edge up a point or two.
CDC Fact Sheet
- May 3, 2014
- 58,402
- Pool Size
- 6000
- Surface
- Fiberglass
- Chlorine
- Salt Water Generator
- SWG Type
- Pentair Intellichlor IC-40
That is with 0 CYA. With CYA, there is negligible difference.
Pool Water Chemistry
This thread presents my findings so far on pool water chemistry including the following: More Accurate Calcite Saturation Index (CSI) to replace Langelier Saturation Index (LSI) Calculation of ppm HOCl (disinfecting chlorine) at various levels of Total Free Chlorine (FC) and Cyanuric Acid (CYA)...
www.troublefreepool.com