View Full Version : pH--soda ash vs baking soda

06-08-2006, 11:49 AM
You said to chime in more often so here I go! :-)

Inground 32,000 gal. vinyl

FC 5
CC 0
pH 7.2
Alk 110
CYA 20

First question: I have had a cloudy appearance to my pool lately so have been trying to shock more, but can't seem to get it to stay. Then I tested my CYA and in two weeks it had dropped from 50-20. What's up with that?

Second question. What is the difference between soda ash and baking soda? I use Mike's calcualator (BTW LOVE IT!!!! THANKS MIKE!!!!) and haven't had to raise my pH, just lower it with Muriatic Acid. He says to use Soda Ash. I have baking soda, but not soda ash....is it interchangeable? I don't really want to mess with my Alk because I think it is fine where it is, so if I understand this method correctly I shouldn't be using Borax unless I want to alter my Alk, right?

Any suggestions or guidance??? Thank you all for your help. You guys are great!


06-08-2006, 12:01 PM
Borax will raise pH, baking soda will raise Alkalinity and I believe that Soda Ash will raise BOTH pH and Alkalinity so it looks like you need Borax if you want to raise your pH.

As far as the CYA, did you do the test the same way in the same place both times? I did a CYA test a few weeks ago that game me a reading of around 40 then I did a reading a week or so later that was only in the mid-twenties but when I thought about it, I did the test in two different places and I didn't pay attention to the amount of lighting available in both cases so I think that was my problem. Lighting will affect how well you see the black dot so that's important.


06-08-2006, 02:30 PM
Strictly speaking both borax and soda ash can raise T/A too. But soda ash will raise it more. Normally, as pH goes up and down it changes the T/A as well. But, by adding soda ash, for any give pH, the T/A will be higher.

If you want to raise your pH without raising your T/A, you have a 3rd option: Since your pH is 7.2, if you aerate your water your pH will rise cost-free without adding anything and without raising your T/A. You can aerate by leaving it uncovered, by pointing your return eyeballs near or at the surface, adding a small fountain, or just leaving it uncovered with the pump running. A crowd of kids works too, but only if you are convinced your water is clean of contaminants.

06-08-2006, 07:31 PM
My PB also said that, if you have a spa spillover, you can crank up the spa returns so that you get a lot of spillover, which will aerate the water better than the "dribble-over".

06-08-2006, 08:19 PM
airating is not without a price. It will slightly lower the TA while it raises the pH....which technique you use (borax, soda ash, airating) really depends on how much impact you want it to have on the TA
Soda ash raises both pH and TA fast
Baking soda raises ph slightly and rasies TA fast
Borax raises pH while only slightly raising TA
Airating raises pH while lowering TA, how much it lowers the TA is dependant on what the pH is when you start airating. the lower the pH the more you will lower your TA to get to the same target pH

Hope this isn't too confusing!:eek:

06-13-2006, 11:57 AM
I've been using Washing soda for PH. It's 100% sodium carbonate.

You can buy it at the super market.

Is Borax the same chemical?

06-13-2006, 12:23 PM
No, borax is borax. :D

Borax is a somewhat generic name used to describe a number of closely related minerals or chemical compounds:
Anhydrous borax (http://en.wikipedia.org/w/index.php?title=Anhydrous_borax&action=edit) (Na (http://en.wikipedia.org/wiki/Sodium)2B (http://en.wikipedia.org/wiki/Boron)4O (http://en.wikipedia.org/wiki/Oxygen)7)
Borax pentahydrate (http://en.wikipedia.org/w/index.php?title=Borax_pentahydrate&action=edit) (Na (http://en.wikipedia.org/wiki/Sodium)2B (http://en.wikipedia.org/wiki/Boron)4O (http://en.wikipedia.org/wiki/Oxygen)7 5H (http://en.wikipedia.org/wiki/Hydrogen)2O (http://en.wikipedia.org/wiki/Oxygen))
Borax decahydrate (Na (http://en.wikipedia.org/wiki/Sodium)2B (http://en.wikipedia.org/wiki/Boron)4O (http://en.wikipedia.org/wiki/Oxygen)7 10H (http://en.wikipedia.org/wiki/Hydrogen)2O (http://en.wikipedia.org/wiki/Oxygen))And there ya go.

Also, that washing soda (soda ash) is going to crank up your alkalinity. That's why most folks here use borax for pH control.