New plaster pool: pH keeps rising

[FloridaRes]

Hi all,

I have a new pool (NTB Mini Pebbles) with plaster installed two months ago. I am very attentative with the chemistry, and measure most parameters several times a week. I feel that pH keeps crawling every time I adjust it to 7.5 it gets up to 8.3 or so within 4-5 days. So I am probably adding 3 quarts of M.A. every week to a 10.000 gal pool. Is that normal, since its a new pool, and the plaster is very alkaline?

The other parameters are quite stable over the last 4 weeks:
Tot. Alk: 100 ppm
TDS: 3100
Chlorine: 3,0 ppm (with a SWG)

Thanks...

 

[PoolStored]

Yes it is normal, and CAN take up to 18-24 months for the pH rise to slow. Typical is 6-12 mos. Rare is 3 years.

Your TA of 100 is also contributing to the rise. Adjust your pH to 7.2 instead of 7.5 for a couple weeks until your TA is between 60 and 80...that will help slow some of the pH rise.

 

[FloridaRes]

Yes it is normal, and CAN take up to 18-24 months for the pH rise to slow. Typical is 6-12 mos. Rare is 3 years.

Your TA of 100 is also contributing to the rise. Adjust your pH to 7.2 instead of 7.5 for a couple weeks until your TA is between 60 and 80...that will help slow some of the pH rise.

OK, thanks. thats just what I needed to know.

 

[PoolStored]

After your TA is 60-80, then revert to process of lowering pH to 7.5/7.6. Don't continue practice of lowering to 7.2.

 

[Bperry]

Hi all,

I have a new pool (NTB Mini Pebbles) with plaster installed two months ago. I am very attentative with the chemistry, and measure most parameters several times a week. I feel that pH keeps crawling every time I adjust it to 7.5 it gets up to 8.3 or so within 4-5 days. So I am probably adding 3 quarts of M.A. every week to a 10.000 gal pool. Is that normal, since its a new pool, and the plaster is very alkaline?

The other parameters are quite stable over the last 4 weeks:
Tot. Alk: 100 ppm
TDS: 3100
Chlorine: 3,0 ppm (with a SWG)

Thanks...

Get your chlorine up as well unless your not using stabilizer.