Help with quickly rising ph??

[cbaird99]

I joined TFP and got Pool Math app last August after struggling for years to do my pool with way too much help and expense from Leslie's Pool store! I got the Taylor 2600 kit, stopped using the tabs and started with just liquid chlorine and liquid acid. I have been really happy with how the pool has slowly become more balanced, except for the last few months I cannot seem to control my ph. I used to only need to add acid maybe 1-2 times a month, now it is every 2-3 days! Here is an example:

5/11/20, FC 3.5, Ph 7.4 (after adding acid earlier that day), TA 70, CH 300, CYA 30.
5/13/20 FC 3.5, Ph 8, TA 70

Now that I have with time gotten my CYA down from about 90 when I started here to 30, my chlorine amount has lessened. The TA has been running at 90 for several months but a month ago it was 80 and now is running 70....is this related? Help??

 

[thetekgeek]

TA and PH go hand in hand. Lower TA and your PH rise should slow down. TA will come down naturally as you add acid to bring down the PH. You could try to force your TA down to 60, or even 50. Or, you could wait and add acid when needed and let the TA drop on its own. How high are you letting the PH get before dropping it? Some pools just like being around 7.8. You could let it rise to 8 and then start dropping to only 7.8 or 7.6. That might help curb the acid demand. I see no sense in trying to keep it at 7.4 if the pool would rather hang out around 7.8.

 

[ping]

Do you have any features that add aeration to the water such as waterfalls, bubblers, etc.?

 

[cbaird99]

TA and PH go hand in hand. Lower TA and your PH rise should slow down. TA will come down naturally as you add acid to bring down the PH. You could try to force your TA down to 60, or even 50. Or, you could wait and add acid when needed and let the TA drop on its own. How high are you letting the PH get before dropping it? Some pools just like being around 7.8. You could let it rise to 8 and then start dropping to only 7.8 or 7.6. That might help curb the acid demand. I see no sense in trying to keep it at 7.4 if the pool would rather hang out around 7.8.

I am lowering the Ph when it is "8" although to me the water sample looks redder that the 8 markings on the testing container. On all my chemical additions, I am aiming for the number my pool math app tells me to achieve...is this wrong? IDK what algorithm the app is using to tell me what to do. This is confusing as it is giving my a target of 7.4 but also a message that my target is outside the ideal range. Am I supposed to be setting my own targets??

It will be swimming season soon and I just want the water to be safe and not irritating to the skin of my young grandkids.

 

[JJ_Tex]

As long as you are waiting until it hits 8, and knock it down to 7.4, that is good. We sometimes see people obsess trying to micro manage their pH and keep it withing a small window. Just keep in in the 7's and you are good.

I'm curious how you answer the question on the water features, as those can drive up pH.

 

[Richard320]

The difference now is that you're not using trichlor tablets. If you were following Leslie's advise in the past, you were feeding the pool a steady diet of them. They are very acidic, so they kept pH and TA in check.

Twice a week doesn't seem extreme to me for adding acid. I have learned that on my pool, every time I add a couple inches of water I have to add a quart of acid. And that can be twice a week in the summer.

As others mentioned, get the TA a little lower and the interval may stretch some.

 

[cbaird99]

Do you have any features that add aeration to the water such as waterfalls, bubblers, etc.?

No nothing like that and my pool gets very little use, none at all yet this year.

 

[markayash]

The difference now is that you're not using trichlor tablets. If you were following Leslie's advise in the past, you were feeding the pool a steady diet of them. They are very acidic, so they kept pH and TA in check.

Twice a week doesn't seem extreme to me for adding acid. I have learned that on my pool, every time I add a couple inches of water I have to add a quart of acid. And that can be twice a week in the summer.

As others mentioned, get the TA a little lower and the interval may stretch some.

Thanks for posting that, I was reading this thread because my PH creeps up also..And I did switch to e SWG this spring
Nothing drastic but stayed steady before and I do have a water fall off the spa.