Does lowering PH with Muriatic Acid affect Alkalinity levels

[jgofnj]

Test resluts:

FC: 8
CC: 0
PH: 7.8-8.0
TA: 80
CH: N/A (vinyl)
CYA: 70

My PH has been slowly creeping up over the past few weeks and I want to lower it a bit. If I use Muriatic Acid, will that affect my alkalinity levels? Alkalinity is a little low. Worried if I lower PH then increasing Alkalinity my PH with rise back up.

 

[YippeeSkippy]

Yes adding MA does lower TA. But your TA is okay, it can be okay down a bit too. Some folks find that a slightly lower TA helps their pH stabilize. Its a matter of trial and error and seeing where your pool's "sweet spot" is.

Try taking your pH down to 7.6 and see if that helps.

Remember that aeration in a pool, such as kids splashing, fountains or other water features running all raise the pH. So adding a bit of acid now and then is necessary for some pools.

Maddie

 

[domct203]

Test resluts:

FC: 8
CC: 0
PH: 7.8-8.0
TA: 80
CH: N/A (vinyl)
CYA: 70

My PH has been slowly creeping up over the past few weeks and I want to lower it a bit. If I use Muriatic Acid, will that affect my alkalinity levels? Alkalinity is a little low. Worried if I lower PH then increasing Alkalinity my PH with rise back up.

I would recommend that you check CH at least once or twice a season, even with a vinyl pool. While low CH is never a problem for vinyl, high CH is an issue with all pools for calcium scale.

What is your fill water CH?

 

[jgofnj]

Yes adding MA does lower TA. But your TA is okay, it can be okay down a bit too. Some folks find that a slightly lower TA helps their pH stabilize. Its a matter of trial and error and seeing where your pool's "sweet spot" is.

Try taking your pH down to 7.6 and see if that helps.

Remember that aeration in a pool, such as kids splashing, fountains or other water features running all raise the pH. So adding a bit of acid now and then is necessary for some pools.

Maddie

Thanks Maddie

- - - Updated - - -

I would recommend that you check CH at least once or twice a season, even with a vinyl pool. While low CH is never a problem for vinyl, high CH is an issue with all pools for calcium scale.

What is your fill water CH?

Thanks Dom. I agree and usually check it once in a while but forgot to today when I posted this. My CH is usually in the 100-150 range.

 

[Richard320]

Acid sure does lower TA.

If you play with pool math some, you'll see that to get the same pH drop at various levels of TA requires differing amounts of acid. So as the TA drops, so does the amount of acid to lower pH. Generally as the TA lowers, the time it takes for pH to rise gets longer and longer. You're well above the minimum TA, so enjoy the pool and stop worrying about insignificant stuff.

Something else to play with: Effects of Adding Chemicals down at the bottom of poolmath. The pH calculation there is only accurate within some very barrow parameters, but the TA drop from adding acid is right. Next time you calculate an acid dose, see what kind of TA drop comes with it. Odds are, it won't even be enough to register on the TA test.

 

[jgofnj]

Thanks Rich