Sodium hypochlorite and PH levels

[Manslick]

I’m putting this is the chlorine section because that is the only thing I have added to the pool since I opened it, not counting the spring opening kits from Leslies.

My concern is really about PH. Will sodium hypochlorite raise the PH level, all other things being equal?

I ask because the PH has risen from 7.6 to 7.8. The only other thing I know of that has entered the pool is some rain on Friday night, about a half inch according to the weather man.

Thanks

[aylad]

It will cause a very temporary increase, but as the chlorine is broken down by stuff in the water, the byproducts negate the higher pH, so as an end result it shouldn't change.

If you have any aeration (a heavy rain that bubbles at the surface, or splashing kids in the water, would do it) in the pool, or a SWCG, those are common culprits for rising pH, as well as higher pH in fill water.

Janet

[Manslick]

Oh yeah aeration. It had to aerate the pool during that rain Friday night.

Thanks J.

[CarlD]

That's it. Just that simple. Bleach/LC is effectively pH neutral. The ONLY thing it adds is a little bit of salt, but 10 years of using bleach won't even begin to put enough salt in the water for a salt water chlorine generator to operate.

Carl

[Manslick]

That's it. Just that simple. Bleach/LC is effectively pH neutral. The ONLY thing it adds is a little bit of salt, but 10 years of using bleach won't even begin to put enough salt in the water for a salt water chlorine generator to operate.

Carl

Thanks Carl.

[Manslick]

Okay I’m starting to freak out a little. Aeration raises pH. That must have something to do with oxygen. If the pH keeps going up, at what level do I act to bring it down? What’s the tipping point?

[Watermom]

Higher than 7.8.

[Manslick]

Thank you.

[aylad]

Many pools have a pH at which they like to "settle"--my pool wants to stay at 7.8 no matter what I do or how many splashing kids I have in it...I spent the first few years fighting it with acid to get back down to 7.4 or so, adjusting alk, etc. and finally just realized that if I left it alone, it would stay at 7.8. (My fill water is 7.8).Been there now for the last 4 or 5 years with no help from me. So....don't panic, just test every day or so to see if it stops at 7.8 or if it keeps rising. If it does,, then you can lower it with acid. If it doesn't, then you can relax and not worry about it.

Janet

[Manslick]

I know what you mean about the pool wanting to be at certain levels. I’ve served this one for 16 years.

But this year I’m using this new method so I have a bit of trepidation since I really don’t know what I’m doing yet.

I’m still foggy on how Sodium hypochlorite can be pH neutral when everywhere I look on the net I see it has a pH of 9 to 13. I truly believe Carl when he says it’s neutral, but I don’t understand all this conflicting info.

I don’t understand how aeration raises pH. It must have something to do with oxygen.

Oh, so much water, so little time.

[CarlD]

Ah, Grasshopper! Very astute question!
Chlorine itself in the water is VERY acidic. Gas chlorination (don't try this at home) can drive pH through the floor!
The acidity of the chlorine in the water and alkalinity of the bleach neutralize each other! So it has zero impact on pH!

Aeration has to do with getting the CO2 out of the water... a little like making soda flat when it loses it...CARBONATION!

(ah the Great Circle of Life for us poolowners! :) )

[Manslick]

Ah, Grasshopper! Very astute question!
Chlorine itself in the water is VERY acidic. Gas chlorination (don't try this at home) can drive pH through the floor!
The acidity of the chlorine in the water and alkalinity of the bleach neutralize each other! So it has zero impact on pH!

Aeration has to do with getting the CO2 out of the water... a little like making soda flat when it loses it...CARBONATION!

(ah the Great Circle of Life for us poolowners! :) )

Thanks again Carl for a very easy to understand explanation.

Probably the nth time you’ve done that.

[CarlD]

That's me!
Simple.....:)

Carl