Pool is happy at 7.9 pH…do I fight it?

[convan23]

Pool is still new / getting ready for our first season (plastered in November). Over the winter pH has been super stable at around 7.9 (color between 7.8 and 8.2 on the K1000 and a repeatable 7.9 on a digital meter). If I was going off of the K1000 alone, about half the time I’d say the pH was 7.8 and the other half the time 8.2. CSI was great with the cold water and higher pH, so I’ve left it like this.

I know we’ve just started getting somewhat warmer weather out here, but I’ve gone a few week long sprints of keeping the pool water heated and even with the water heated at 85 the pH is still constant around the same.

I can add ~10oz of acid in the morning, and 24 hours later the pH is right back at 7.9. I can also not add acid for a week+ and pH is still 7.9 or so.

Should I consider dropping TA some more?
So I consider borates?
Should I be happy with a 7.8+ “happy state”?

Like any new “hobby” of mine…I’m fighting the urge to try and control every variable I can vs letting things go and letting it ride. Thanks for the insight!

 

[mknauss]

Do not mess with a good thing. If the pH is stable, in the 7's, and does not cause eye or skin irritation, leave it be.

 

[ajw22]

Go swim and stop tinkering. Find other things to work on in the house.

Your water chemistry is fine.

 

[HeyEng]

Mine also likes hanging around 7.9-8.0'ish. I did fight it for a bit, but gave up as my CSI really stays close to 0 with me not touching it and it stays nice and clear.

 

[convan23]

Thanks all! Thanks for the reassurance.

 

[generessler]

Mine is very similar although it takes 3-4 days to get from 7.3 to 7.9, not one. If the swg is running it tends toward 8.0 even. In that case I bump it down on Friday evening before the grandchildren come over just to be safe, even though we've never had any problem.

 

[kul]

Mine also remains in the 7.8-8.2 range. I’ve tried bringing it down but it always pops back up. Similar to you, my CSI is in range and no swimmers seem bothered so maybe it’s ok. Though I just started testing and managing my pool in December so will see what the warmer weather brings.

 

[Leebo]

What may I ask is your calcium level? I ask as I may buck the trend some and suggest a lower pH if your calcium is higher?

 

[kul]

I’d be interested in your CH level too. Mine is 225 at last check.
@Leebo should ph be lower at a certain CH measurement?

 

[convan23]

Yeah, you can check my pool math logs for CH. Last check at 450.

@Leebo should ph be lower at a certain CH measurement?

CH raises CSI. High pH raises CSI. Higher temperature raises CSI. So high CH, pH, and Temp can equal high CSI.

I added calcium in the winter to keep CSI neutral. It’ll creep back down.

At pH 7.8, CH 450, temp 95 my CSI is still only 0.15. So not too high and within a normal range. If I let the CH creep down to like 350, CSI is a nice neutral 0.04. So all still feasible.

 

[kul]

At pH 7.8, CH 450, temp 95 my CSI is still only 0.15. So not too high and within a normal range. If I let the CH creep down to like 350, CSI is a nice neutral 0.04. So all still feasible.

Thanks for sharing these numbers. I have a similar sized plaster pool so this is super helpful.

 

[Leebo]

Yeah, you can check my pool math logs for CH. Last check at 450.

I was crossing my toes those were the right numbers. Sounds like your new hobby of pool care is gonna turn out to be kinda boring…….just the way we like it.

 

[convan23]

Thanks for sharing these numbers. I have a similar sized plaster pool so this is super helpful.

If you download poolmath you can pretty easily play with numbers and see what your CSI results in - just tap the CSI box and it’ll open a screen where you can see how different levels impact CSI.

It’s helpful to play out some what ifs. Like over the winter when water was really cold I was able to see the easiest thing to maintain a neutral CSI was to raise the calcium level.

 

[kul]

I have pool math but I hadn’t tested different scenarios based on season and my increasing CH! Great idea.