What makes TA rise?

[nauidvr1]

What makes my TA rise? After spending almost a week adding Muratic Acid and then aerating, repeating & repeating, I was able to get my TA to lower from 110 to about 75-80. Now 10-12 days later the TA has risen to 100 again. I have added about 1 inch of make up water and we had 2 thunderstorms, that added about 1.5 inches of water to the pool - is the rain the culprit?

I have borates in the pool (about 35ppm), and it is my understanding that it will now be harder to lower the TA level. So before I start the process again, and also finish adding borates to 50ppm, I thought I would ask if it is necessary to lower the TA again? Thanks.

 

[JohnT]

Rainwater doesn't raise alkalinity directly, but it can raise pH either through the pH of the water or through aeration of the pool. When pH goes up, TA goes up too. Comparing TA readings over time isn't very useful unless you record pH at the same times.

 

[dmanb2b]

John, would aeration created by rain raise TA? I thought aeration on it's own does not raise TA. To the OP...you could try to sample some rainwater and test the TA of the sample, but as John mentioned it's unlikely the culprit.

Have you had any borax/baking soda/ph+ additions lately?

 

[dschlic1]

While rain by itself does not effect TA, rain can and will wash dust and dirt inot your pool. These can have an effect on the TA. My pool was a cse in point. For many months my TA was at 80 ppm. After the first hard rain of the season, the TA when up to 100! pH readings were the same.

 

[nauidvr1]

I don't think Aeration raises TA, but it does make pH rise. I did have a hard rain and I also power washed the concrete deck around the pool. I tried not to get much of the washoff from the deck into the pool, but some may have gotten in. This might be why my TA has risen, between the rain & the power washing.

Now that I have borates in the pool will it be harder to lower my TA? I think I want to try to get the TA back to 70-80 if possible - or is it necessary?

 

[dmanb2b]

if at 100 you are not experiencing nagging PH rise...the TA is fine. Remember the TA we advocate is a guideline...each pool is slightly different. If you do experience frequent PH rise at 100, you would benefit from lowering your TA further.

 

[nauidvr1]

No, I am not experiencing a nagging pH rise at all, if anything it is a little low right now (7.4) due to the recent rain. I was going to aerate later today to get it up to 7.7.

So I will just leave TA alone for now - Thanks!

 

[lovingHDTV]

My TA rises from the fill water.

Did you add fill water either manually or via automatic water topoff?

dave

 

[nauidvr1]

My TA rises from the fill water.

Did you add fill water either manually or via automatic water topoff?

dave

Read above - yes, atleast 3 ways, Rain, from the hose & also power washing.

 

[lovingHDTV]

My TA rises from the fill water.

Did you add fill water either manually or via automatic water topoff?

dave

Read above - yes, atleast 3 ways, Rain, from the hose & also power washing.

Have you tested the TA of your fill water? Mine is 200+, that was my point. I guess I did not say that very well

dave

 

[nauidvr1]

Have you tested the TA of your fill water? Mine is 200+, that was my point. I guess I did not say that very well

dave

Dave,
Ah, no I didn't - I have "city" water - but have not tested it.