Jump to content

PH and Alkalinity balance - Not as easy as it sounds


Rcf

Recommended Posts

Hello, this is my first post. 
 

I need some advise on how to balance Ph and Alkalinity in my spa. The tap water in my area is high in Ph and the alkalinity is about 60. I know in order to keep the Ph levels in the correct range I should address the alkalinity first, or so I’ve read. When I do that the Ph goes up, and when I try to bring the Ph down the alkalinity goes down. How do I achieve balance without having to play this ping pong game every week? Thanks!

Link to comment
Share on other sites

What is your sanitizer?  Bromine
 

What is your pH? It tests 8.2+ out of the tap, the TA tests at 60 or 70
 

How are you testing pH and TA? A standard testing kit, not strips 

 

Note - I am in South Florida. They add a lot of liquid chlorine to our water because it comes from the Biscayne Aquifer and it is naturally brownish. This is an aesthetic thing, but I understand liquid chlorine has a Ph of 13 and that may be why our water Ph is high. 

Link to comment
Share on other sites

If I were you, I would try lowering my TA down to 60 initially and see if the ph will follow it down to <8.  If not, come down to 50 (not sure that I would go any lower, perhaps @waterbear might chime in and offer better advice) and check ph again.  If >7.6 and <8 you are in business.  If it falls below 7.5 you can aerate to bring it up.  

If you cannot get below 8 with a TA of 50, then hopefully someone else on the forum can advise.

The only other random thought I have is that your pH test is off for some reason (ie. old reagents, other contradictions such as high sanitizer levels).  If possible, try testing with another kit or take somewhere for a second data point.  What is your bromine level?

Link to comment
Share on other sites

Interesting that you mentioned the reagents. Mine have been around for a while and they are kept in the garage at the mercy of the temperatures there.  I purchased new reagents today and the results were exactly the same. So much for that. 

I’m trying small amounts of muriatic acid to see if it will  bring down the stubbornly high Ph. I know this will lower the TA too, but I understand I can bring it up a bit with baking soda which should only raise the Ph slightly.

As for the TA, it comes out of my tap at 60. Interestingly enough there seems to be two schools of thought regarding TA. One is that low TA will create unstable Ph so the TA needs to be 100 to 150 ppm. The other opinion, which I have seen several places to include this forum is to forget about TA and simply concentrate on Ph. No wonder people are confused about spa chemistry.  

To answer your other question, my bromine levels are right on the money  

 

Link to comment
Share on other sites

  • 2 weeks later...

What brand and model of testing kit are you using? (It does matter!)

Read these posts!!!!!! They will provide some background info (based on the actual chemistry that goes on in the water)

https://www.poolspaforum.com/forum/index.php?/topic/52522-some-truths-about-ph-and-ta/

https://www.poolspaforum.com/forum/index.php?/topic/28846-lowering-total-alkalinity-howto/

 

On 10/26/2022 at 8:46 AM, Rcf said:

Note - I am in South Florida. They add a lot of liquid chlorine to our water because it comes from the Biscayne Aquifer and it is naturally brownish. This is an aesthetic thing, but I understand liquid chlorine has a Ph of 13 and that may be why our water Ph is high. 

They actually add chlorine and ammonia . They do this because the monochloramne produce is more stable than just chlorine. As far as the pH of liquid chlorine it it net neutral (alkaline on addition, acidic on consumption) so it really has minimal impact on pH. This is also true for cal hypo.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.

Guest
Unfortunately, your content contains terms that we do not allow. Please edit your content to remove the highlighted words below.
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...