pH fluctuating up and down this year

[Toad_stools]

Hi guys. This year pool has been pretty easy to manage. Been able to keep things in check for the most part. However, one thing I have noticed the past 2 or 3 weeks is that I’m having some problems keeping the pH stable. Usually in the morning it is 7.0, I try and aerate it through the day by angling the jets up for some splashing, which does help a bit. I have added a bit of baking soda last week and then pH was 8.0. I didn’t do anything to it and then couple mornings later was back down to 7.0. I haven’t added anything to it again but it seems to be up and down everyday between 7 and 8. The only thing that seems to be different this summer is that I noticed the last few readings for TA it is slightly higher than what it was last summer. Right now it is around 110 or 120. Last summer was about 90 or 100. It just seems like the buffering capability is not where it should be. Thoughts? TIA.

 

[Texas Splash]

Right now it is around 110 or 120. Last summer was about 90 or 100. It just seems like the buffering capability is not where it should be. Thoughts?

Focus on the pH. When it exceeds 7.8, lower it a little, to say 7.5 or 7.6, but don't try to force the pH down to 7.0 right now. Your TA is okay. Some pools like a TA around 100, some pools like a TA around 60. It all depends on how fast your pH is rising. In your case, it sounds as though your pH isn't rising too quickly, so just add enough acid to lower the pH a little. Slow & steady should work.

 

[Toad_stools]

Focus on the pH. When it exceeds 7.8, lower it a little, to say 7.5 or 7.6, but don't try to force the pH down to 7.0 right now. Your TA is okay. Some pools like a TA around 100, some pools like a TA around 60. It all depends on how fast your pH is rising. In your case, it sounds as though your pH isn't rising too quickly, so just add enough acid to lower the pH a little. Slow & steady should work.

Thanks TS. Good to hear the TA is OK. I thought maybe that might be the prob. It just seems like last summer I’d be able to keep it steady for a week, but this summer it drops overnight a fair bit. I bring it back up to optimal range over a day or two, couple times it did get too high, then drops again quickly. I did add a bit of acid the one time, but the last few times it has dropped quickly on its own. Maybe it’s not that odd just different than what I remember from last summer. We’ve had a few rain events the past couple of weeks that come in bursts so maybe that is also affecting? Thanks.

Edit to say other than that the pool has been crystal clear all summer and I don’t mind having to manage the pH like this if that’s all that’s going on!

 

[Texas Splash]

but the last few times it has dropped quickly on its own.

That's definitely in the minority as most pools the pH tends to increase over a few days. Something to watch. If you are adding new water each week for top-offs, perhaps test your fill water pH and TA to see if they are low. That might explain it.

 

[Sunnydaze]

Something acidic has to get into the water to lower the ph. Are you supplementing chlorine with tabs? No acid or "ph down" has been added? It would take a lot of acid to get it from 8 to 7 multiple times. What are you using to test pH?

 

[Toad_stools]

Something acidic has to get into the water to lower the ph. Are you supplementing chlorine with tabs? No acid or "ph down" has been added? It would take a lot of acid to get it from 8 to 7 multiple times. What are you using to test pH?

The only thing I can think of is the rain we have gotten lately. It has rained in the night a few times. Downpour for 10 or 15 minutes.

I test with a Taylor CK 2006 kit. I don’t add anything except a couple weeks ago I added some muriatic acid when it was 8.0.

Seems strange no? Like this morning it was below 7.0. We had rain last night as well.

 

[mknauss]

Are you testing the water after the pump has run for 30 minutes or so?

Some rain fall can be acidic, but not that acidic.

 

[Toad_stools]

Are you testing the water after the pump has run for 30 minutes or so?

Some rain fall can be acidic, but not that acidic.

Ah. Good question. This morning no. It rained last night, I turned the pump on this AM, and I tested it right away. I didn’t even think of that. Sometimes the simplest explanation alludes me!! It’s been running a few hours now I will check it again. Thx.

 

[Toad_stools]

Well guess what. It’s now 7.8.

Edit: This makes me realize that last year I was consistently taking samples in the evenings, and for some reason this year I’ve been doing it in the AM. Unreal!

 

[Texas Splash]

Well guess what. It’s now 7.8.

It can become a cat & mouse yo-yo game if you let it. Just manage the pH as noted above and you should be fine. Don't overreact with large chemical doses.

 

[Toad_stools]

Hopefully some people will learn from my dumb mistakes! Although I don’t think this one was quite as embarrassing as when I thought there was something wrong with my skimmer (just needed more water in the pool!). Thanks guys!

 

[Texas Splash]

Although I don’t think this one was quite as embarrassing as when I thought there was something wrong with my skimmer (just needed more water in the pool!).