Balancing alkalinity and PH

[Kelly001]

Two questions — do I increase alkalinity before addressing the PH?

Is sodium hydrocarbonate ok to use instead of baking soda? I bought it last year at a pool store and it is branded as “alkalinity rise”. This forum has taught me to be skeptical of everything I’m doing.

Thanks in advance!
Kelly

 

[PoolStored]

Two questions — do I increase alkalinity before addressing the PH?

At 50, you are ok...just don't drive your ph below 7.8/7.9...just let it sit there. If you are super worried, raise it to 60 with baking soda. Not hydrocarbonate.

If it does rise to 8.0, then only reduce it to 7.8, don't drive it down to 7.6.

 

[Kelly001]

Thanks, a related question— I was following the pool math app recommendations to raise it to 70. And, also to lower the PH. Should I ignore their recommendations? This isn’t the first time someone in the forum has given me different advice than the app.

 

[PoolStored]

Sorry for all the confusion, we are getting into "nuance corner."

Any TA above 50 is fine, below 50 you need to raise it. 60-80 is a great range.Any pH in the 7s is also fine. It is about finding the balance.

High TA and/or Low pH will cause rapid pH rise. It is about finding the balance.

The app is intended to provide advice across most pools and is accurate.

Where you get into the "bump," is when you try to keep TA low (60-70)...AND drive pH down to 7.6 or below. When you do that you reduce TA at the same time, potentially forcing TA below 50 by forcing pH down.

With TA of 60-80, pH will tend to stabilize between 7.8 and 8. (even pH of 8 is ok).

Get your TA to 60-80, and then let pH stabilize, and see where it ends up. Don't force it down to 7.6 to meet poolmath recommendation...again, 7.8-8 is fine.

More reading:

PH TA Relationship - Further Reading

www.troublefreepool.com

 

[Kelly001]

Thank you! This forum is so helpful!!