pH "Control"

[lucas70]

Hey Everyone. A fairly new pool owner (approx. 2 years). I am having an issue with pH control, or so I think. Why I say I think is because I have read some posts where people have to add very little muriatic acid/pH lowering chemicals to their pool. Seems their pH stays steady for the most part. I check my pH at least 2 times a week and it seems like I'm anywhere from 7.8 if I'm lucky to 8.0 or 8.1. It seems I am adding 24 ounces of acid to my pool at least 2 times a week, if not more. I guess my first question is, is that more than normal?

A few things to note. All of my other numbers are within normal range when I test. One exception is my alkalinity, which is low at times. But I have to believe this is because as I'm adding acid I'm lowering alkalinity and it naturally becomes low at some point in the process, at which time I'm adding baking soda. I live in Texas and needless to say it is scorching heat. I was wondering if that plays a part in this. Additionally, I was wondering if the the pool jets/returns aimed toward the surface of the pool may be impacting this, as well as possibly the in floor cleaning system? Lastly, I generally use liquid chlorine (10 percent) to sanitize, but at times use calcium hypochlorite. I generally just keep one chlorine table in my chlorinator set at a low level as I don't want my CYA to creep up too high.

Any help would be appreciated. Thanks for any advice anyone can give.

 

[JJ_Tex]

Hey Lucas - Welcome, couple of questions:

1. What is your TA?
2. What is the source of your test results? (what type of kit, pool store, pool guy, etc)
3. At what point do you lower pH (when it hits 7.8, 8.0, above 8?)
4. When you lower your pH, what do you lower it to?
5. Do you have any water features or anything that would aerate the water?

 

[lucas70]

JJ_Tex:

Thank you for the welcome, and thank you for the response.

1) My TA is generally around 100. However, it is hard to maintain at 100 since I'm adding a lot of acid. Or what I think is a lot of acid.
2) I use a LaMotte Color2x kit. I do have it checked at a pool store every so often, and the results are mostly in line. I trust my kit more though.
3) I only lower pH if it gets above 7.8.
4) I am lowering to 7.4/7.5. I generally add 24 ounces of acid when I need to lower pH.
5) I have 2 water features but generally do not run them. I was wondering if the in floor cleaning system, which I run every day, could be aerating the water and contributing to this.

 

[Jimrahbe]

70,

As long as your TA is above 50, I would not do anything to increase it..

I try to run my TA at about 50 as that helps me keep my pH in check. Even so, I add about 22 oz. of MA to my pool each week.

Thanks,

Jim R.

 

[JJ_Tex]

A TA of 100 isnt terrible and I would not worry about it as long as it is above 50.

Also know that pH rise isn't linear. When I lower mine to 7.4, it will be back to 7.8 in a few days but it loves to hang out between 7.8 and 8.0 for days or even weeks at a time.

I would leave your TA alone and only add acid when you hit 8.0 or even a bit higher. Then just knock it down to 7.6. That should really lessen your acid usage and frequency.

Here is the link on the various recommended levels if you want:

What Are My Ideal Pool Levels?

Use our tool to find ideal chemical levels for any swimming pool. Check TFP recommended levels on pH, free chlorine, cyanuric acid, and more.

www.troublefreepool.com

 

[lucas70]

Thank you for the replies. Especially the chart. That may be where I'm going wrong so to speak. Thinking my numbers are abnormal when they really are not that abnormal. In other words, making adjustments when their really not needed.