New Pool Readings - Potential Issues?

[ripcurlvb]

I've got a new 11,000 gunite pool that was plastered (LunaQuartz) and filled on 6/24. The pool builder has been maintaining the pool - yesterday I tested the water with the TP-100 kit and got the following:

FC = 0
CC = 0
pH = 7.4

I didn't measure anything else, but called the pool builder. They sent a pool cleaner out, and he added chlorine and acid. This morning at 0800, I got the following numbers

FC = 20
CC = 1.5
pH = 4.6 (with a pH meter)
TA = 110
CH = 175
CYA = 50

I went back out at 1400, and got the following

FC = 1
CC = 0
pH = 4.5
TA = 0
CH = 350
CYA = 40

I have a call in with the pool builder, but seeing as it is a holiday weekend, I don't expect anything until Tuesday. Is there something that I need to do now to try to raise the pH?

 

[ajw22]

I think you need to understand what startup process your builder is following.

Plaster Start-Up Guides - Further Reading

www.troublefreepool.com

Check your testing methods as CH is not likely to go from 175 to 350 in 6 hours. And your FC and CC change does not seem reasonable.

Water Testing Errors - Further Reading

www.troublefreepool.com

Did you calibrate your pH meter with 7.0 and 10.0 calibrating solutions?

What pH meter do you have?

 

[kimkats]

Turn you returns up so they roll the water good and hard! That will be a start.

Do you have any water features like a spa overflow or such? If so turn it on so it is really hitting the water hard.

I will be back in a min to give some more ideas.

 

[ripcurlvb]

Thanks for the help. I will check to see what kind of startup they are using.

The pH meter is the one that came in the TF-Pro kit. I did not calibrate it. But when I tested TA, the water turned red when I added the R-0008.

There definitely could be some user error in the first CH reading - I remember wondering if I had performed it correctly.

As for the FC, it took me 40 drops of R-0871 to get it to clear up. Again, there could be some user error. I just tested it again, and the sample stayed clear after adding R-0870, so I assume I have 0 FC.

I will turn on the fountains and let them run for a while to see if that helps, and run a full battery or tests again later this evening.

 

[ajw22]

The pH meter is the one that came in the TF-Pro kit. I did not calibrate it.

That meter is not very high quality.

But when I tested TA, the water turned red when I added the R-0008.

That means you have a TA of zero.

It sounds like they are doing an acid start-up.

Start-up Chemistry for Plaster Pools The effects of four different chemical startup procedures were studied.

• the “Acid” startup – where enough acid was added to lower the pH to 4.5 and alkalinity to zero - about 3 gals. of acid per 10,000 gallons of water
• the “pH-Neutral” startup – which equates to about one gallon of acid is added to about 10,000 gallons of water
• the “Traditional” startup - where the water is maintained with CSI balanced water; near zero or (0.0) CSI
• the "Bicarb" start-up - where the tap water is pre-treated with sodium bicarbonate to raise the TA to 300 ppm and the CSI is about +0.6 to +1.0