New pool numbers

crabboy

LifeTime Supporter
Jul 24, 2007
528
Suwanee, GA
#1
Using the test kit by PB gave me; here is everything I could test this am:

FC 2-3
PH 7.8
TA 40
CYA 70
Water temp: 89
Daytime temp yesterday was 103.

I tested yesterday and the PH was off the chart, I added a quart of acid and rested a few hours later and added another 2 cups. These are the numbers from this morning. From the suggestion of the acid-demand test, I added another 2 cups of acid before leaving for work. My PB said that the pool would require a good bit of acid the first month.

The FC took a good dip between the am reading and the 6pm reading. I was 3+ yesterday am and around 1 at 6pm.

Should my FC and TA be higher?

Pool is a new IG gunite, 21k.
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#2
With CYA of 70 you want to keep FC above 5 at all times. It is normal to lose FC to sunlight each day. I wouldn't expect the loss to be quite that large, but wait till you bring the FC level up to more reasonable levels and see what that does before worrying about it.

Fresh plaster will raise the PH rapidly for the first few weeks and then continue raising PH more slowly for perhaps a year. You need to keep a constant eye on the PH at first to be sure it isn't going too high. Don't hesitate to bring the PH down as low as 7.2, that will give you a little more time before you need to add acid again. With a little more experience you will get a better idea of how much acid that takes. Just keep in mind that the amount of acid required will increase as the TA increases. The rate of PH rise will also slow a little as TA rises.

I wouldn't worry about TA or hardness for the first several weeks. As the plaster cures they will both come up. Most new plaster pools end up at reasonable values by the end of the first month.
 

crabboy

LifeTime Supporter
Jul 24, 2007
528
Suwanee, GA
#3
Thanks Jason. I was aiming for 7.2 when I added acid this morning. The test the PB gave me will only test the FC up to 3, seems pretty weak that it'll only test to 3 or am I missing something?
 

JasonLion

TFP Expert
Platinum Supporter
LifeTime Supporter
May 7, 2007
37,879
Silver Spring, MD
#4
Only testing to 3 is fairly useless, but not all that uncommon. 5 is a slightly more common limit. Neither one is really what you want, though they can be very handy for a quick check to be sure FC hasn't dropped towards zero. You also need a calcium hardness test, it doesn't matter this month but will become important later.

You should invest in a good test kit, one with a FAS-DPD chlorine test that works up to 50 and shows FC and CC separately. The TF Test Kit, see the link in my signature, is a good choice and the Taylor K-2006 also has the appropriate tests. A good test kit is the best investment in your pool you can make.
 

ktdave

LifeTime Supporter
May 8, 2007
888
Katy, TX
#5
Congratulations on gettin her started up Crabboy! Yeah, the pH in a new plaster pool is bit of a bear. I've only been operating just over 3 weeks now and I've gone through 5 gallons of 31% muriatic. Although in the last few days, I haven't had to add any, which before, I had to add it everyday. It seems to be starting to stabilize.

I agree with Jason on getting Dave's TF Test Kit.
 

crabboy

LifeTime Supporter
Jul 24, 2007
528
Suwanee, GA
#9
TF kit numbers:

FC: 7.5
CC: ~.5
PH: 7.8
TA: 40
CH: 110
CYA: 20-30

The CYA test showed questionable results. The kit the PB gave me shows the CYA to be about 50. The old test has a plastic stick that I move up or down with the gauge on it. I kind of like that one better since I can move it around w/o moving the liquid.

I added acid as usual.