TA doesn't seem to change how often I add MA

[voidpointer]

My plaster pool completed at the beginning of March this year. It's now June, and my TA has gone from 110 to 60 naturally. I believe I'm getting to the low end of the target range for my pool. Ever since I've started doing chemical maintenance on my pool, it has demanded around 32oz of MA every 2 days. This hasn't changed throughout the 110 to 60 change in my TA.

The further reading page for TA explains that a lower TA should mean fewer acid additions, but I'm not observing that. What could explain the reason for the lack of change in acid demand? Is this a characteristic of new plaster pools (that they will demand acid regardless of TA level for the first year)?

BTW: My poolmath logs are available for viewing if needed.

 

[mknauss]

Is this a characteristic of new plaster pools

It is. Be sure you limit any aeration (water features). Also fill water likely has TA in it.
Also let the pH rise to 8 and only lower to 7.6.

 

[voidpointer]

My test kit has 7.8 and 7.5. After I add, I go from 8.2 to 7.5 typically. This is every two days.

I setup spillover mode on my aqualink specifically to cut down on water features. Now I run my sheers and slide for 5 minutes every day and the spillover twice a day, each for 20 minutes. Other than that, there's no aeration.

 

[JamesW]

Your CH is going up with no calcium added, which might indicate dissolving plaster.

 

[JamesW]

Rapid pH increase with SWCG

Guys, I'm losing my mind with this pool. I've scoured all the threads on this topic here and in other forums. I've tried every "remedy" I could find, and yet, here I am, dumping gallons of acid in at a time only to come back a few days later to pH > 8.0. I've always felt I was very diligent with...

www.troublefreepool.com

 

[voidpointer]

Your CH is going up with no calcium added, which might indicate dissolving plaster.

Is there anything I need to do to investigate that or change the behavior?

 

[JamesW]

This post covers dissolving plaster.

Rapid pH increase with SWCG

Guys, I'm losing my mind with this pool. I've scoured all the threads on this topic here and in other forums. I've tried every "remedy" I could find, and yet, here I am, dumping gallons of acid in at a time only to come back a few days later to pH > 8.0. I've always felt I was very diligent with...

www.troublefreepool.com

 

[voidpointer]

This post covers dissolving plaster.

Rapid pH increase with SWCG

Guys, I'm losing my mind with this pool. I've scoured all the threads on this topic here and in other forums. I've tried every "remedy" I could find, and yet, here I am, dumping gallons of acid in at a time only to come back a few days later to pH > 8.0. I've always felt I was very diligent with...

www.troublefreepool.com

I clicked that before but it's 9 pages! Can you point me to a specific post to start reading from?

 

[JamesW]

If the TA rise is from calcium carbonate from the plaster, you will get the same ppm increase in calcium hardness as you get in TA.

So, monitor the CH and TA to see if they rise by the same amount.

If they do, then that points to calcium carbonate.

 

[JamesW]

I clicked that before but it's 9 pages! Can you point me to a specific post to start reading from?

Read the whole thing.

 

[mknauss]

I suspect your fill water has CH in it. Have you been adding fill water due to evaporation?

 

[JamesW]

What are the TA and CH of the fill water?

 

[voidpointer]

I suspect your fill water has CH in it. Have you been adding fill water due to evaporation?

I leave my autofill on 24/7. It's always running just a little bit because of constant water evaporation. I have not run a test on my tap water. Should I do that? And would I run all of the tests or just CH?

If the TA rise is from calcium carbonate from the plaster, you will get the same ppm increase in calcium hardness as you get in TA.

So, monitor the CH and TA to see if they rise by the same amount.

If they do, then that points to calcium carbonate.

I have data in Pool Math from March this year to show if there's a correlation. I haven't bothered to check since I wasn't aware of the relationship. I'll go back and try to make sense of what I've already recorded.
When you say "TA rise", does that mean the number is getting *lower*? For example, going from 110 -> 60 is a "rise"?

And none of this behavior has to do with the plater only being 3-4 months old?

 

[JamesW]

TA rise means getting higher, but you are adding acid, which is lowering the TA, so you have to account for the acid effect.

 

[voidpointer]

Just did the tests on tap water:
TA: 90 (80 made the solution clear, one more drop made it pink, so I went with 90)
CH: 125

 

[mknauss]

So your fill water effects your TA and CH levels.

 

[JamesW]

Can you track how much fill water is added per day?

 

[voidpointer]

So your fill water effects your TA and CH levels.

My TA I wasn't so concerned with, as my understanding is that it goes down over time as I add MA. So I figured the fact that it is at 60 is not unexpected.

What does concern me is the pH still requiring additions twice a day. But you said it's not unexpected due to the new plaster, so I figured the post was done and over with, and there were no issues.

However the CH is being brought up as an issue. It's gone from 275 in March to 425 now. If my tap water is 125, does that have an additive effect over time? When the water evaporates, is the calcium left behind, so the tap water continuously causes a build up?

Can you track how much fill water is added per day?

I have no way to measure that.

 

[JamesW]

When the water evaporates, is the calcium left behind, so the tap water continuously causes a build up?

Correct.

Try to keep the CSI as close to 0.0 as possible.

 

[mknauss]

It's gone from 275 in March to 425 now.

That is way more than from fill water.