Advice on lowering the PH but not taking down the alkalinity at the same time

[Aquatub88]

I have a question on maintaining a steady PH without messing with a perfect alkalinity reading.
My PH is showing a little high on the test strips as well as the Taylor chemical test (I use both to cross check the accuracy). The alkalinity is right around 90.  I use the Hotspring PH down which also influences the alkalinity and brings that down concurrently. How can I bring an 8 reading on the PH down without messing with the alakalinity?  My fear is that the ph will come down to 7.6 to 7.8 and the alkalinity will drop also under what is acceptable?  Looking for thoughts and experience.  Thank you.

[castletonia]

Not possible.  pH down, and or muriatic acid are the only ways to lower pH and both will also lower Total Alkalinity.

[Aquatub88]

Ok, so if you take down the PH which also will take down the alkalinity, what is the best way to bring the alkalinity back up without moving the PH?  Is that doable?  Thank you...

[bradleyabell]

Ok, so if you take down the PH which also will take down the alkalinity, what is the best way to bring the alkalinity back up without moving the PH?  Is that doable?  Thank you...

PH and Alkalinity natually pull on each other, so if say, for example, PH is high and ALK Is OK...If you use PH Down it will lower ALK and PH and then the higher PH will pull ALK back up and hopefully balance both.

[The Wizard of Spas]

I have found that the most effective way to reduce pH/Alkalinity is to add the product to the water (irrelevant if it is sodium bisulfate or muriatic acid) and leave the jets OFF.  You'll get a greater rate of reduction vs. turning the jets on.  To be clear, adding your reducing agent and turning on the jets is totally fine.  Just doesn't work as effectively.

If both pH and alk are low, increase the alk first and most times the pH will rise as well.  If you just need to increase pH only, you can leave the air portals open, as aeration can increase pH.  However, I cannot speak to the effectiveness of this tactic in specifics.  I would say that it doesn't really work as good as just adding pH increaser, though.

Lastly, if you use Potassiumperoxy Monopursulfate aka Oxidizing Shock/Spa Shock, that has a pH value of approx. 2.3.  Thus, adding that in can give you a reduction in pH as well. 

Hope this helps.  Good luck moving forward.

[bradleyabell]

I have found that the most effective way to reduce pH/Alkalinity is to add the product to the water (irrelevant if it is sodium bisulfate or muriatic acid) and leave the jets OFF.  You'll get a greater rate of reduction vs. turning the jets on.  To be clear, adding your reducing agent and turning on the jets is totally fine.  Just doesn't work as effectively.

If both pH and alk are low, increase the alk first and most times the pH will rise as well.  If you just need to increase pH only, you can leave the air portals open, as aeration can increase pH.  However, I cannot speak to the effectiveness of this tactic in specifics.  I would say that it doesn't really work as good as just adding pH increaser, though.

Lastly, if you use Potassiumperoxy Monopursulfate aka Oxidizing Shock/Spa Shock, that has a pH value of approx. 2.3.  Thus, adding that in can give you a reduction in pH as well. 

Hope this helps.  Good luck moving forward.

Totally agree about jets off...My local spa company has me do this: pull around 5 gallons water out of tub into bucket...Pour what you need from your PH/ALK reduction product into bucket and mix well.  Then pour water mix into middle of tub and turn off tub completely and let sit for 2 hours, then retest...If more needed, redo.

[Jacuzzi Jim]

 Or just leave it alone, and not worry about it.  Unless it's off the charts a little high PH is not a problem, and will come down on it's own.  Specially if you are using chlorine. 

[wmccall]

Or just leave it alone, and not worry about it.  Unless it's off the charts a little high PH is not a problem, and will come down on it's own.  Specially if you are using chlorine.

I subscribe to this ideology.  Though I'll admit to just keeping the PH near normal and not worrying about alkalinity.  I can tell when my PH is too low easily enough though.

[Chas]

I have found (here in SoCal) that they almost always go up and down together. However, if one is high and the other is low, it usually means it's time for a water change. We are in a drought here, so I find all kinds of odd chem issues, and it is getting harder and harder to convince folks to change their water at all, let alone four times per year. But if your water is older than three months, consider it a good USE of water to change it out. Not a waste of water at all!

If your water is less than three (or even less than two) months, then lower pH with some form of acid, and a day or so later, raise the TA with baking soda (sodium bicarbonate).

HTH

[wmccall]

I have found (here in SoCal) that they almost always go up and down together. However, if one is high and the other is low, it usually means it's time for a water change. We are in a drought here, so I find all kinds of odd chem issues, and it is getting harder and harder to convince folks to change their water at all, let alone four times per year. But if your water is older than three months, consider it a good USE of water to change it out. Not a waste of water at all!

If your water is less than three (or even less than two) months, then lower pH with some form of acid, and a day or so later, raise the TA with baking soda (sodium bicarbonate).

HTH

Chas lives?