New pool help

[Gooseafcrna]

Our pool was just finished this week, wet edge pebble and filled 2 days ago. Of course, the PB told me to do what he said this week in order to start up the pool and maintain pebble warranty. We want to use the TFP method, but kind of had to go with his start up. He told us to add 1 gallon muriatic acid, 1 gallon of shock, and 10 pucks to the chlorinator. I questioned him on these steps since I used my new TF-100 kit and my pH was about 7.6 last night, but he said to "trust him". So,my results tonight:

Ph:6.8 or less!!
Cl: 6.5 by drop test.

How should I get the pH up? My kids really wanted us to be able to swim tomorrow because I leave for 8 weeks of training and a 6 Monty deployment on Sunday.

I assume my Cl will go down since I don't have any CYA in the water and we get full sun for about 6-8 hours a day, but should I take the pucks out of the chlorinator tonight? Or just leave a couple? I figured that the pucks would at least put some CYA in the water. The chlorinator is on setting 5. Any help is appreciated. BTW, the pool is about 14,500 gallons.

Eric

 

[aasbury]

Follow your builder's directions to the letter or you might void your warranty. Those pucks are adding CYA along with chlorine. You need CYA in your water if it is a fresh fill.

 

[pooldv]

There are 3 ways to raise PH
Aeration
Borax
Soda ash

Pool School - Recommended Pool Chemicals and how to add them.

use Pool School - PoolMath to calculate how much to add. Be sure to enter your TA number too.

It would be good to read this too, Pool School - ABCs of Pool Water Chemistry

 

[Gooseafcrna]

Thanks Pooldv. I've read through most everything a time or two, but somehow missed the pool math page. I added borax as calculated, minus a few oz's since I can always add more. Any advice on the pucks? I don't want to use them, but the PB is insistent.

 

[aasbury]

If you have any kind of warranty, you need to follow the builder's advice...

 

[Gooseafcrna]

I added the Borax as per the pool math calc and yesterday morning we were at:
pH: 7.5-7.8
Cl: >5
We swam most afternoon with several people in the pool, full sunlight. Values last night at 7:
pH: > 8.2
Cl: 0
CC: 0.5
TA: 90
CYA: 0
Used calculator and added 21oz Muriatic acid, PB called and said to add a bottle of shock. About 2 hours later out pH was 7.5 and Cl obviously high.
This morning we are at:
pH: just less than 7.8
Cl: 11 by drop test.

We still have the 9 pucks in the chlorinator per the PB. I know that the chlorine will be down again later today d/t the sun, but how long does it take for the pucks to deposit CYA in the water so we can hold on to the chlorine and get it down to a better level? They are trichlor. Any other suggestions appreciated.
Eric

 

[pooldv]

It is fine to use pucks to chlorinate and raise your CYA up to 50 ppm. It will also help lower your PH right now. New plaster pools will have PH rising fast. It is important to lower PH to 7.2 when it gets to 7.8.

At the bottom of Poolmath is a section Effects of adding chemicals that will tell you what change to expect when adding something to your pool. I believe that each puck adds 6 or 7 ppm of CYA. So, calculate how much CYA 9 pucks gives you and add some granular CYA in a sock to get CYA up faster to give some protection from the sun.

- - - Updated - - -

Add bleach when FC drops below minimum to get it back to target quickly. Definitely do not want the pool sitting with less than minimum FC, Chlorine CYA Chart. It is safe to swim when FC is above minimum and below shock level. So, it is much better to have FC at or above target than to have it down near minimum.

Also, here are the Pool School - Recommended Levels for your pool.

 

[Gooseafcrna]

Thanks for the help. Another question:
Tonight, our pH is 7.5 and TA is 60. We know the pH will rise over night, but if we get it down with muriatic acid then out TA also goes down and we will be chasing that. What's the best way to deal with each one without causing a problem with he other? Thank you.

Eric

 

[pooldv]

Usually it is best to work the PH and let the TA work itself. PH and TA will normally find an equilibrium. Having a newly finished pool adds an extra twist with the additional acid demand. But, it is most important to keep PH between 7.2 and 7.8 and secondarily important to maintain TA. Also, adding baking soda does not raise PH much, 32oz of baking soda to 15k gallons raises TA by 9.5 and PH by .02. So, keep an eye on TA and if it drops to 55 add a lb of baking soda.

Keep an eye on the CSI in Poolmath and keep it between -.5 and +.5. Tweaking PH, TA and CH moves this number around. Enter your current number in Poolmath and change the targets to see what CSI does.