New pool check in - 3 weeks post startup

[WorkingNotTo]

Hi, all, and thank you for this forum. We just had our first pool installed and started up 3 weeks ago and are learning lots from this great site.

I just got my TF-100 test kit and did my first full round of testing.

FC - 4.0
CC - 0
CYA - < 20
PH - 7.7
TA - 50
CH -175

I have a couple of questions about the results.

Our salt startup is in about 10 days and we are chlorinating with pucks until then. Should we start to raise our CYA now or wait? The startup guide from our builder recommends 30 - 50 ppm, so we have room within their recommendations.

The builder recommends TA of 80 - 120 after the second week but we've needed to add lots of muriatic acid to keep the PH close to range. I'm not sure 80 - 120 is reasonable? We do have a sheer decent we have been leaving off for most of the day. Should we leave it on for aeration to try to bring the number up?

Do you have any other advice or suggestions based on the above numbers?

 

[HermanTX]

Welcome to TFP.
You will find that our chemical levels will be somewhat different from the “industry”. This is because the industry assumes most pools are chlorinated with pucks. Pucks have CYA (an acid) as well as chlorine which keeps pH in check but continues to add CYA.

Did your read through Pool Care Basics

Most start up recommendations suggest a minimum of TA 80.
The CH will need to be increased to above 250 if you have a plaster pool.
Continue to use pucks to bring up CYA
You mention adding salt in 30 days but you do not indicate if you have a saltwater chlorine generator (SWCG). Please add that info to your signature.
Follow FC/CYA Levels
Also use this What Are My Ideal Pool Levels?
Also download the app - PoolMath and track your testing levels there.

 

[Newdude]

Hey WNT and belated Welcome !!!


All of that above from Herman ^^^^^^


But I'd Overnight Chlorine Loss Test before raising the CYA. Once it's raised your slam target jumps 4FC for every 10 CYA and it gets expensive and tiresome quickly trying to SLAM the higher FC. Once you raise it after passing the OCLT, it's critical that you don't hit min after todays UV loss. Or any day.


Slam is the same but here's both charts because you'll be leaving LC soon.

Do you have any other advice

I would do as the PB / manufacture says for the startup period. Refuse any chemical/puck that mentions Blue or XtraBlu as it's likely laced with copper.

Once they turn it over to you, we'll guide you the rest of the way.

Aim for the lower TA recommendation and it will help keep the Ph down a little.

 

[HermanTX]

The builder recommends TA of 80 - 120 after the second week but we've needed to add lots of muriatic acid to keep the PH close to range. I'm not sure 80 - 120 is reasonable? We do have a sheer decent we have been leaving off for most of the day. Should we leave it on for aeration to try to bring the number up?

Have you tested your fill water? That will indicate if your replenishment will affect TA and CH levels.
Aeration does not increase TA, but it will increase pH. I would avoid aeration at this time because your TA is on low end and your pH is fine for now. I would wait to your pH is 8.0 or 8.2 before adding an muractic acid (MA). You may not need to add any MA if your pucks keep your pH in line. Also the low TA is minimizing the rise in pH. Each pool is different so test daily and post those results.

 

[pjt]

I just got my TF-100 test kit

Great choice. Do you have a SpeedStir or other type of stirring device?

TA - 50

Are you continuing to add drops until there's no additional color change? When I test TA, it takes ~3 more drops after the color begins to change until I reach the end of the test.

The builder recommends TA of 80 - 120 after the second week but we've needed to add lots of muriatic acid to keep the PH close to range.

That TA recommendation assumes the use of trichlor tabs, which are acidic. With LC or SWCG, a TA ~60 will give you pH stability in the high 7s. TA down to 50 is perfectly fine. What startup guide are you using? Follow the startup guide to completion, then transition to TFP chemistry guidelines.

Trying to maintain a TA in the 80-120 range with a stable pH in the mid 7s a fool's errand. You'll endlessly chase your tail adding baking soda and MA.

What's the TA and CH of your fill water?

Plaster Start-Up Guides - Further Reading

www.troublefreepool.com

What Are My Ideal Pool Levels?

Use our tool to find ideal chemical levels for any swimming pool. Check TFP recommended levels on pH, free chlorine, cyanuric acid, and more.

www.troublefreepool.com

Our salt startup

What SWCG do you have? Heater? Add it to your signature.

 

[WorkingNotTo]

Thanks all. I’ll test the fill water and work on the calcium hardness this afternoon. Then do an OCLT tonight before taking on the rest tomorrow