New pool - plaster startup questions

[Blackdirt Cowboy]

We are starting construction on our new pool next week. I guess I’m jumping the gun a little, because I’m already researching plaster startup. I’ll be using this guide, as we are installing NPT stonescapes, and this is what they recommend:


It says on day one to reduce TA to 80ppm and pH to 8.2. It also says on day 2 to add calcium to a minimum of 150, and after the 4th day to slowly add calcium to no more than 200 ppm over the course of 28 days.

Here’s the conundrum. My fill water is already a pH 7.2 with a TA of 340 ppm and 250 ppm calcium. There’s no way to get TA down to 80 without dropping pH well below 7.2. Not to mention my calcium level will start above the 28 day maximum.

Does anyone have any advice on what I should do?

 

[ajw22]

There are alternative startup procedures.

Your fill water chemistry is perfect for the bicarb startup where you want TA +CH to be around 500...

A Bicarb Start-up guide for TFP members

It is an unfortunate fact that most tap water used to fill swimming pools is often soft, aggressive, and somewhat harmful to a new plaster surface. Therefore, in order to not damage a new plaster surface, the tap water needs to be “balanced” (meaning for new plaster, the CSI should be at least...

www.troublefreepool.com

@onBalance developed the process and is usually around to answer question.

Plaster Installation and Maintenance - Further Reading

www.troublefreepool.com

 

[Blackdirt Cowboy]

Thanks! It does look like my fill water is perfect for that method. If I’m understanding correctly, I wouldn’t even have to add any sodium bicarbonate to water as my TA + CH is already greater than 500 ppm. Looks like I’ll only have to adjust pH downward as it creeps up. If my TA drops due to the acid treatment to where TA and CH combined become less than 500 after the pool is filled, would I then need to add sodium bicarbonate to make up the difference for the first few weeks?

 

[ajw22]

I doubt you would need to add bicarb since you are starting at about 600 and the process works down to 400.

 

[onBalance]

In case you haven't, I would advise that you double check the readings of your tap water just to be sure.
If your tap water does have those numbers, you won't be able to reasonably follow the NPC startup guideline.

Therefore, the program to follow is to add acid as much as is reasonable which slowly lower the alkalinity level over time. I believe it will take some weeks to lower the TA below 150 ppm which is just fine.

The empirical evidence for over 50 years and shown that the Bicarb program works very well for all plaster/cement finishes. And No additional bicarb should be needed.

 

[Blackdirt Cowboy]

I ran the tests on my fill water twice just to double check. I’m pretty confident in the results as they were identical on both tests. I’m actually pretty excited as it seems all I really need to worry about is not letting the pH get too high over the first month. Of course I will dose and monitor chlorine, and CYA. And I understand that can be started as soon as the pool is full, is that correct? Also, is it still standard practice to wait 30 days before adding salt?

 

[onBalance]

I agree that watching and controlling the pH rise is the important issue.
Follow the NPC program for chlorine and CYA additions as they are reasonable.
Do not add salt until 30 days has past.

 

[ajw22]

I ran the tests on my fill water twice just to double check. I’m pretty confident in the results as they were identical on both tests. I’m actually pretty excited as it seems all I really need to worry about is not letting the pH get too high over the first month. Of course I will dose and monitor chlorine, and CYA. And I understand that can be started as soon as the pool is full, is that correct? Also, is it still standard practice to wait 30 days before adding salt?

I do suggest you read the link I gave you above. It gives many tips on how to have a quality plaster job…

Plaster Installation and Maintenance - Further Reading

www.troublefreepool.com

 

[Blackdirt Cowboy]

Working on it. It’s a LOT to get through.