Can not get pH to come down

[crosby1612]

I'm having trouble getting my pH down despite the addition of muriatic acid every day.

Using the TF Pro Salt test kit, these are my numbers: pH 7.8 - 8.0 (I'd like it to be 7.5-7.6), CH 400, TA 90, FC 8, CYA 70, Salt 3.1

Following the PoolMath app, I've added between 8 and 12 oz of MA everyday for the past few weeks and the pH just doesn't budge.

Any thoughts?

Thank you.

 

[PoolGate]

Add more? I add until the pH test is orange. I also never measure it at all. Just dump until it seems correct. After awhile you'll have an understanding of how much your pool needs.

 

[Bperry]

I'm having trouble getting my pH down despite the addition of muriatic acid every day.

Using the TF Pro Salt test kit, these are my numbers: pH 7.8 - 8.0 (I'd like it to be 7.5-7.6), CH 400, TA 90, FC 8, CYA 70, Salt 3.1

Following the PoolMath app, I've added between 8 and 12 oz of MA everyday for the past few weeks and the pH just doesn't budge.

Any thoughts?

Thank you.

A better target would be 7.8 as the farther you lower the pH, the faster it rises. Sounds like you just need more acid or its rising fast.

 

[Newdude]

How old is the pool ? New pools can have a healthy MA demand for the first year while the plaster cures.

Any water features ? Aeration greatly affects PH rise, such as waterfalls or spa spillovers. We advise flushing them once or twice a day for 15 mins then only using them when you're out there to enjoy them. No need to have them work against you the other 99% of the time.

Then trying to maintain a lower PH will make it swing faster as well. Many subscribe to the disproven theory that lower PH makes chlorine more efficient, which it does when there is no CYA, but CYA mitigates the effects down to about 15%. So it's much less of a deal and then they need far more acid to maintain the lower Ph more or less making it a wash. It's kinda robbing Peter to pay Paul.

 

[SecoSteve]

Three things could be contributing to this.

1. Are you using 31.45% Muriatic Acid or half strength, maybe "Green"?

2. Your pool volume is higher than you think.

3. Your Ph is higher than you think, and it is only coming down to 8.0 with acid additions.

 

[crosby1612]

Three things could be contributing to this.

1. Are you using 31.45% Muriatic Acid or half strength, maybe "Green"?

2. Your pool volume is higher than you think.

3. Your Ph is higher than you think, and it is only coming down to 8.0 with acid additions.

31.45% MA
I'm fairly certain on the volume; it could be 12k but not more than that

 

[crosby1612]

How old is the pool ? New pools can have a healthy MA demand for the first year while the plaster cures.

Any water features ? Aeration greatly affects PH rise, such as waterfalls or spa spillovers. We advise flushing them once or twice a day for 15 mins then only using them when you're out there to enjoy them. No need to have them work against you the other 99% of the time.

Then trying to maintain a lower PH will make it swing faster as well. Many subscribe to the disproven theory that lower PH makes chlorine more efficient, which it does when there is no CYA, but CYA mitigates the effects down to about 15%. So it's much less of a deal and then they need far more acid to maintain the lower Ph more or less making it a wash. It's kinda robbing Peter to pay Paul.

The pool is brand new. No water features. I guess just keep adding acid?

 

[Newdude]

The pool is brand new.

Ok so it'll want some MA for a while.

guess just keep adding acid?

Yup. As you manage the ph the TA will fall to 50 or 60 and help keep the PH lower. Dose at 8+ and only to 7.8. You can target a low 7 for now to speed the TA drop, but it's half a dozen or six if you just let it happen on its own.

 

[SecoSteve]

So chalk it up to a new pool, rising Ph. My pool is going on its 4th season and this is the first season my Ph has not been constantly rising. It seems to have settled down. It still heads over 8, but I just bump it down to 7.6.

My first season I was thinking bring Ph way down(low 7's) and it will take longer to go over 8. That was wrong. I ended up lowering my TA to much. I used way too much Muriatic Acid back then. Shoot for 7.6 and enjoy your pool!!