Liquid chlorine raising ph??

[dford8583]

I was at a Leslie’s pool store trying to return this 50lb bucket of cal hypo. They wouldn’t let me return in because of their policy. Ok then.. but the guy asked me why I am wanting to return. I said I wanted to go the liquid chlorine route because that is what I have been reading in some books and on this forum.
The guy says that liquid chlorine raises the ph because it has a ph of 13. He also said that when using liquid that it burns off in like a couple hours. This is counter to what I have read and researched. I am currently at another pool store about to fill up some jugs of liquid chlorine right now but wanted to ask about this now. I plan on checking/adjusting pool chemistry regularly. Is this guy blowing smoke because their store does not sell liquid chlorine?

 

[mknauss]

Liquid chlorine is pH neutral. When it is added to the pool it does not effect your pH.

As long as you have a level of CYA recommended by TFP, and follow the FC/CYA Levels, you will lose about 2-4 ppm FC per day during swim season.

 

[Texas Splash]

The guy says that liquid chlorine raises the ph because it has a ph of 13. He also said that when using liquid that it burns off in like a couple hours.

Pool store advice? Ahhhhhhh! Chlorine in high amounts can raise the pH a little, but that effect is temporary as the pH will return to normal as the FC drops. The PoolMath tool or APP will tell you the amount of pH increase expected based on how much chlorine you add. As for the burn-off ... hog wash. FC falls based on the amount of CYA, water temp, direct sunlight, etc. Doesn't matter how it was introduced (liquid, tabs, powder, SWG, etc).

I use liquid chlorine 365 days a year. No problem.

 

[mknauss]

pH effect by liquid chlorine

Above is a link to a thread in Pool Water Chemistry. It helps explain why the liquid chlorine does not effect your pool water pH.

 

[dford8583]

Thanks y’all. This is what I suspected but I wanted to field the question. I am using pool math and about to subscribe today so I can log my numbers.

 

[Leebo]

As for the liquid chlorine "burning off" in a few hours......he's kinda right.......but not telling the entire story. If anything, when using liquid chlorine you may see the FC burn off in a matter of minutes depending on how strong the sun is that day. Even on a cloudy day you'll likely see the FC drop rather fast. Now the part they really left out. This mostly only occurs IF you're not adding CYA to the water. If you follow our levels and add CYA to at least 30ppm you'll see the CYA "protect" the chlorine. This will greatly reduce the amount of chlorine loss you'll see every day.

He's not wrong.......but not right either.

 

[JamesW]

Calcium hypochlorite and sodium hypochlorite are both unstabilized hypochlorite types of chlorine.

They both have the same pH and effect on pH on addition. The pH mostly goes back down as the chlorine gets used up.

Calcium hypochlorite has more of a pH effect than sodium hypochlorite.

In addition, calcium hypochlorite has insoluble dust that clouds the water for hours and leaves precipitate on the bottom of the pool.

Calcium hypochlorite is much more likely to cause issues with staining because it can drop to the bottom without dissolving.

Unstabilized chlorine get stabilized very quickly when there is cyanuric acid in the water.

The fact that they sell calcium hypochlorite while disparaging sodium hypochlorite is ignorant.

 

[ajw22]

What is the Effect of Adding Liquid Chlorine on pH?

 

[dford8583]

thanks for the input everyone. I did buy some liquid chlorine and am stuck with this 50 lb tub of cal hypo so I guess I will get to experience both. I am going to be draining the pool this weekend to get rid of the excess CYA and bring it back down to 30 to start the season.

 

[mknauss]

In your climate I would suspect you get pretty good water turnover due to rain at times. Thus you should be able to use the cal hypo up over time.

What pool type do you have? Can you fill out your signature?

 

[dford8583]

Liquid chlorine is pH neutral. When it is added to the pool it does not effect your pH.

As long as you have a level of CYA recommended by TFP, and follow the FC/CYA Levels, you will lose about 2-4 ppm FC per day during swim season.

In your climate I would suspect you get pretty good water turnover due to rain at times. Thus you should be able to use the cal hypo up over time.

What pool type do you have? Can you fill out your signature?

I filled out some in my signature. I will get more specifics when I get to my pool equipment