Can't keep my TA and pH down

[Needsdecaf]

OK, so I've been running on the SWG for a few weeks now. Still getting it dialed in. This past week was cloudy and rain on and off, so my FC consumption dropped, and my FC level spiked up over 10. Dialed back the SWG a few notches and now it's down to 6.26. Took me a few days to get there though.

The thing that I can't get dialed in is the TA and pH. When my FC was high, I dumped in 32 oz of acid according to pool math and that did indeed get my pH down to 7.2 and my TA down from 116 to 74. However, both have continued to drift up. pH just went from 7.8 to 8 over the weekend and TA is now back up to 108.


Readings today:

FC - 6.26
CC - 0
pH - 8
TA - 108

I don't trust the Color Q for the CYA test, as I've never gotten the CYA above 50, and it has shown a drop - now at 32. I have ordered a TF 100. I have put in about a quart of liquid CYA and am hesitant to put in more without an accurate test. Easy to put in, tough to get out!!!

In any event, going to put some acid in tonight, but what could be causing such a quick rise in pH AND TA? is it the low CYA? The FC spike?

Thanks!

 

[JasonLion]

Do you either have an autofill system or have you been manually adding water to the pool? If so, check the TA of your fill water. High TA fill water would do exactly what you describe.

 

[Needsdecaf]

Do you either have an autofill system or have you been manually adding water to the pool? If so, check the TA of your fill water. High TA fill water would do exactly what you describe.

No, neither. It has been raining a good bit over the last week. Acid rain?

- - - Updated - - -

I should mention that I have not been running the waterfalls all that much. Maybe 30 minutes / day on average, if that. 2 of my 4 jets break the surface, one a tad, and one a bit more.

 

[Needsdecaf]

Well, 32 oz of muriatic dropped the water to pH 7.1 and TA of 82, so I don't have reason to doubt my tester. I will let the pH come back up and tomorrow night throw in some more acid to try and drop the TA down to 60.

 

[Needsdecaf]

Revisiting this thread.

So I finally got my TF-100 and the first results were:

FC 4.5
pH 8.0
TA 80
CYA 60

Dropped that pH with some acid. 3 days later

pH back up to 7.8
TA 40

Dropped the pH back down to 7.4. This was on 7/27.

Today, 7/30, my results:

pH 8.0
TA 80.

My plaster was applied on June 10th.

What gives?

 

[Richard320]

Sounds normal.

No matter what start-up procedure is used, your pool will consume a lot of acid during the first 6-12 months as the plaster finish continues to cure. It is important to test your pH daily and do not let it climb above 7.8. Be sure to continue to brush the pool at least weekly during this period.

http://www.troublefreepool.com/content/154-start-up-new-pool-plaster

 

[pwrstrk]

Your plaster is still curing and your SWG plus a water feature if your using it, will all contribute to your PH rising. Keep lowering your PH when it gets to 7.8-8.0.
You might want to bump your CYA up to 70-80 if your losing more than normal FC. 70-80 is recommended for a SWG.

 

[Readyforapool]

My pool is new this year as well - I've had to add 48 oz of acid every two to three days to keep the ph down. The guys at Lowe's know me by name because I've bought so much of the stuff!

 

[Needsdecaf]

Sounds normal. http://www.troublefreepool.com/content/154-start-up-new-pool-plaster

Thanks! I thought I read someplace that it was only like 1-2 months, not that long.

Appreciated!

It's not a pure plaster finish. It's wet edge pebble / plaster finish. Does that make a difference?

 

[Needsdecaf]

Also, two of my returns break the water. One gently, the other a little more vigorously. My PB said he likes to do this to promote good circulation. Is this good, bad or neither? I have to say, the pool is sparkling clean!

 

[JasonLion]

The first month is the most intense for PH increases, then it slows down and continues for up to a year. A pebble finish is basically the same, but not quite as much PH increase as you would see from plain plaster.

Having the returns break the surface is good if you want aeration, bad otherwise. Unless you have some specific need for aeration you don't want that, and it certainly does not help circulation.

 

[Needsdecaf]

Thanks. I will adjust my returns and see if that helps.

 

[Needsdecaf]

So in speaking to my PB today about another issue, he mentioned that his rule of thumb is for a 10k gallon plaster pool, 1 gallon of MA / Week is average demand.

I think it took me about 3-4 weeks to go through 2 gallons on an 8k gallon pool.

Do either of these seem reasonable?

 

[mrcarcrazy]

So in speaking to my PB today about another issue, he mentioned that his rule of thumb is for a 10k gallon plaster pool, 1 gallon of MA / Week is average demand.

I think it took me about 3-4 weeks to go through 2 gallons on an 8k gallon pool.

Do either of these seem reasonable?

**I'm basing this response on my pool, and the pools of friends locally.**

Your pool builder sounds like mine. He claimed something similar. I use maybe a gal every 2 wks on my 20k pool. Your experience is much more inline with mine than what your PB and mine state to be fact. (my fill water has a pH >8.2) and I have quite a bit of aeration. I've accepted that Acid will be a fairly regular purchase.