PoolMath Ideal pH Level for SWG vs "Water Balance for SWGs" Article

[TygerDad]

I've entered all my pool data into the PoolMath app, including that I have an SWG. The PoolMath ideal range for pH is 7.6 to 7.8, as is also stated in the article: "What Are My Ideal Pool Levels?". The "Water Balance for SWGs" article (Water Balance for SWGs) states "add acid to lower it back to 7.2 – 7.5 (This is also IMPORTANT!)", although it does state you generally want to keep it in the overall range of 7.2 to 7.8. Following the 7.2 to 7.5 range would put it outside of the ideal range in both the app and the recommendation in the My Ideal Pool Levels article. Maybe I missed something, however, it isn't clear to me in all the articles I've read on the site, why the lower pH range 7.2 to 7.5 is critical for SWG pools. Would appreciate it if an expert could clarify it for me. Thanks in advance!

 

[YippeeSkippy]

I'll tell you that the SWG seems to "like" to be around 7.8pH. That's fine if it works well with your TA and if you're monitoring your CSI.

Try this- Using the OLD web version of PoolMath, enter all your current chem levels in to the first column. Then take a look at the CSI. Is it ok?
Then play around with entering variable into the 2nd column and see how it changes your CSI.

PoolMath

Discover the calculator behind the perfect pool, PoolMath. Dealing with pools has allowed TFP to become the original authors of the best calculator on the net.

www.troublefreepool.com

Your pool is plaster so all elements are kinda important to the big picture, BUT they can be tweaked for your convenience. For example folks in the Southwest often have super high Calcium in their fill water. Knowing that they'll have levels FAR over what most folks want they tweak their pH down to help them avoid scale.

Does this help in any way??

Maddie

 

[TygerDad]

Maddie, My CSI in both the iOS app and web versions is -0.25 / -0.26. My current pH is 7.6, FC 6.0, TA 70, CH 350, CYA 70, Salt 3200, temp range 84 to 89 deg, so it's in pretty good balance. I've been using the recommended ranges in the SWG article I referenced (a really good resource!)

If I drive the target pH in the web version down to 7.35 (midpoint of the recommended range in the SWG article), it drives the CSI down to -0.48. I've been working to get the pH down to the ideal range, it was up higher (before the pool service bailed on me and I had to take over managing it ).

What I don't understand is why the recommendation in the SWG article is to drive the ph down to 7.2 to 7.5, which drives the CSI in the wrong direction based a recommended range of -0.6 to 0.6, and is outside of the recommended ideal range.

 

[PoolStored]

All the content on the website and the wiki entries have been written by many individuals, who are all volunteers. There may be minor inconsistencies in the content, which we address from time to time, typically in the off season as we have time. Content is also written in a way that the AVERAGE pool owner will understand and follow...to keep them out of harm's way, for a WIDE variety of pools.

You are certainly advanced in your knowledge and thinking. If you are managing your CSI for scale (wise), then you may manage your levels in a way that may vary from recommended levels to keep YOUR pool in balance.

Hope that helps!!!

 

[wireform]

Tyger,
Try this. Go into the poolmath phone app and open the home page, jot down all your levels on paper then go to "log test results" and enter them in and then look at the CSI on the bottom, you then can play with some of the levels to see which one will bring the CSI more into range.

 

[TygerDad]

All the content on the website and the wiki entries have been written by many individuals, who are all volunteers. There may be minor inconsistencies in the content, which we address from time to time, typically in the off season as we have time. Content is also written in a way that the AVERAGE pool owner will understand and follow...to keep them out of harm's way, for a WIDE variety of pools.

You are certainly advanced in your knowledge and thinking. If you are managing your CSI for scale (wise), then you may manage your levels in a way that may vary from recommended levels to keep YOUR pool in balance.

Hope that helps!!!

Thanks, I'll keep that in mind.

TFP is treasure trove of great knowledge and recommendations, especially since it's been over 30 years since I last had a pool, and pool systems have continued to evolve since then. I appreciate the volunteer effort and contributions. TFP is an outstanding resource and well worth the support.

Perhaps the recommendation to drive the pH down to between 7.2 to 7.5 is to get well ahead of the drift up past 7.8. As I've been balancing my pool, and having watched the previous pool service additions of MA, it seems to need more regular additions MA than some of the other chemicals.

 

[TygerDad]

Tyger,
Try this. Go into the poolmath phone app and open the home page, jot down all your levels on paper then go to "log test results" and enter them in and then look at the CSI on the bottom, you then can play with some of the levels to see which one will bring the CSI more into range.

Thanks, I'll try this.

 

[PoolStored]

Perhaps the recommendation to drive the pH down to between 7.2 to 7.5 is to get well ahead of the drift up past 7.8. As I've been balancing my pool, and having watched the previous pool service additions of MA, it seems to need more regular additions MA than some of the other chemicals.

Now we got something to talk about. Your TA is 90. Over time, with additions of MA, your TA should come down. Do you know your fill water TA? If it is high, it will counteract the lowering of TA with MA.

As your TA is reduced your pH rise will decrease. My TA is 70 and my pool sits at 7.4.

Here's a piece I wrote that can help, since you like to understand the details. Enjoy!

PH TA Relationship - Further Reading

www.troublefreepool.com

 

[TygerDad]

Now we got something to talk about. Your TA is 90. Over time, with additions of MA, your TA should come down. Do you know your fill water TA? If it is high, it will counteract the lowering of TA with MA.

As your TA is reduced your pH rise will decrease. My TA is 70 and my pool sits at 7.4.

Here's a piece I wrote that can help, since you like to understand the details. Enjoy!

PH TA Relationship - Further Reading

www.troublefreepool.com

This is very helpful and very interesting, thank you. Now I understand the drivers. I have lots of aeration (waterbowls, spa spillover, spa air jets, bubblers, SWG). I'll test the TA of the fill water as well.

 

[PoolStored]

I have lots of aeration (waterbowls, spa spillover, spa air jets, bubblers, SWG)

Bingo...so does SWIMMING! Which you should do more of...just sayin'.

 

[mknauss]

In the Pool School articles you referenced, CSI is not discussed. During the last revision of those articles, there are some in the Forum that do not like to force CSI on members. It is too complex, and most users, especially in the South and Southeast, have no need to use it. So the discussion is targeted at those pool owners. Also, in the SWCG article, the pH is suggested to be reduced from 7.8 to the range of 7.2 - 7.5, not kept in that lower range. By doing so, the TA is managed, which is the primary reason that the pH would rise to 7.8 or above.

As folks have mentioned above, you know about CSI, and are comfortable with it. So use that..

 

[mgtfp]

The "Water Balance for SWGs" article (Water Balance for SWGs) states "add acid to lower it back to 7.2 – 7.5 (This is also IMPORTANT!)", although it does state you generally want to keep it in the overall range of 7.2 to 7.8

You have taken this statement out of my its context. The whole thing reads:

Adjust your Total Alkalinity to 60-80 ppm. (This is IMPORTANT!)

Adjust your pH to 7.2-7.8 and not any lower. Monitor your pH and when it climbs to 7.8 add acid to lower it back to 7.2 – 7.5 (This is also IMPORTANT!)

What you were quoting were bits of the instructions how to lower TA, not the recommended pH levels.


A colon would reduce the chances to misunderstand the instructions:

Adjust your Total Alkalinity to 60-80 ppm (This is IMPORTANT!):

Adjust your pH to 7.2-7.8 and not any lower. Monitor your pH and when it climbs to 7.8 add acid to lower it back to 7.2 – 7.5 (This is also IMPORTANT!)


 EDIT:
After reading the article again, forget what I just wrote. Marty nailed it.

 

[TygerDad]

In the Pool School articles you referenced, CSI is not discussed. During the last revision of those articles, there are some in the Forum that do not like to force CSI on members. It is too complex, and most users, especially in the South and Southeast, have no need to use it. So the discussion is targeted at those pool owners. Also, in the SWCG article, the pH is suggested to be reduced from 7.8 to the range of 7.2 - 7.5, not kept in that lower range. By doing so, the TA is managed, which is the primary reason that the pH would rise to 7.8 or above.

As folks have mentioned above, you know about CSI, and are comfortable with it. So use that..

Thanks. I understand that now. I've seen some scaling on the grout and was wondering about it. Now I know to monitor the CSI as well to help prevent that.

 

[TygerDad]

You have taken this statement out of my its context. The whole thing reads:

Adjust your Total Alkalinity to 60-80 ppm. (This is IMPORTANT!)

Adjust your pH to 7.2-7.8 and not any lower. Monitor your pH and when it climbs to 7.8 add acid to lower it back to 7.2 – 7.5 (This is also IMPORTANT!)

What you were quoting were bits of the instructions how to lower TA, not the recommended pH levels.


A colon would reduce the chances to misunderstand the instructions:

Adjust your Total Alkalinity to 60-80 ppm (This is IMPORTANT!):

Adjust your pH to 7.2-7.8 and not any lower. Monitor your pH and when it climbs to 7.8 add acid to lower it back to 7.2 – 7.5 (This is also IMPORTANT!)


 EDIT:
After reading the article again, forget what I just wrote. Marty nailed it.

Thanks, I understand that now. It's a very helpful article and I appreciate you writing it. Perhaps also removing the return and space after the colon would help make it clearer to a newbie (like me!) .