Why increase when using SWG?

[SunnyFL]

We recently moved over to a SWG. Love it! I am trying to understand why CYA and CH increase when moving to salt. Just trying to understand it conceptually.

 

[mknauss]

We recently moved over to a SWG. Love it! I am trying to understand why CYA and CH increase when moving to salt. Just trying to understand it conceptually.

Welcome to the forum!
In the 'Deep End' sub forum there is a sticky called Pool Water Chemistry. In it the following statement explains the need for a higher CYA level in pools that use a SWCG to generate chlorine:
"Salt Water chlorine Generation (SWG) pools seem to require a higher level of CYA, about 70-80 ppm, to operate efficiently. The theory is that the CYA is slow to "store" the chlorine as it is being generated so without enough CYA there is a build-up of chlorine that degrades the performance of the salt cell. "

On the CH level, you will see the SWCG levels show a lower TA. That is because the pH in a SWCG pool tends to rise, which means as you add muriatic acid, the TA falls. The higher level CH is to keep the CSI (Calcium Saturation Index) in the appropriate range. PoolMath calculates CSI for you.

 

[SunnyFL]

Thank you for the detailed explanation! I appreciate it!

 

[jnojr]

The higher level CH is to keep the CSI (Calcium Saturation Index) in the appropriate range. PoolMath calculates CSI for you.

How and where does it do that? I don't see anything like "CSI" or "calcium saturation" in mine, only CH.

 

[mknauss]

How and where does it do that? I don't see anything like "CSI" or "calcium saturation" in mine, only CH.

Are you using the PoolMath app or the web based PoolMath?

If the app, you must go to Pool Setup (the gear looking thing) and go down to Track CSI - and turn it on.

On the website, it is automatically calculated.

 

[ajw22]

How and where does it do that? I don't see anything like "CSI" or "calcium saturation" in mine, only CH.

You have to turn on tracking CSI. Press the wheel in the upper right. Scroll down and you will find additional items to turn on.

 

[jnojr]

Are you using the PoolMath app or the web based PoolMath?

If the app, you must go to Pool Setup (the gear looking thing) and go down to Track CSI - and turn it on.

Ahh, thank you!

On the website, it is automatically calculated.

Where is the web site calculator now? The last time I tried to find it, I just got directed to the app, and figured the web version was gone.

 

[ajw22]

Ahh, thank you!



Where is the web site calculator now? The last time I tried to find it, I just got directed to the app, and figured the web version was gone.

Link is on the bottom middle “Quick Navigation “ on every page. PoolMath

 

[jnojr]

So, tracking CSI requires tracking temperature. I'm not sure how frequently I should be recording temp, or if there's any specific method... just run in pool mode until the indicated temp stabilizes?

 

[mknauss]

Your Intellitouch reports water temperature from a probe in your plumbing. After just a couple minutes of water flowing, the temperature is relatively accurate.

 

[jnojr]

Your Intellitouch reports water temperature from a probe in your plumbing. After just a couple minutes of water flowing, the temperature is relatively accurate.

So, "good enough"? How often should I be checking/logging temp?

 

[mknauss]

I do it when I run my tests and enter it into Poolmath app.