Tap Water Test


Gold Supporter
Mar 22, 2019
Lynchburg, VA
Hello everyone. Been reading and lurking on the board for the past few weeks while our pool is being built.
I’ll update my signature with my pool equipment very soon.
25,000+ gunite pool. All Penair equipment with SWG.
All the equipment was set this week and we’re scheduled for the plaster guys on Monday.
Really excited we are getting close.
In anticipation of filling the pool next week I did a test of my tap water.
I got a result that I was surprised about.
I used the TF-100 test kit and I also purchased a Hach Pocket Pro+.
Here are the results from my tap water.
FC 1.0
CC 0.0
CH 75
TA 40
PH Just under 8.2

Thought the PH didn’t make sense. I grabbed the HACH and got a reading of 8.17
Still didn’t believe it would be that high.
Grabbed the singlets of ph buffer solution (7.0) used for calibration and the HACH came in at 7.01 on it.
So all evidence points to this being correct.

Just looking for any thoughts....
Thanks in advance.

Rocket J Squirrel

Silver Supporter
Bronze Supporter
Jun 7, 2018
Alamo, CA
Your water is fine. My pH from the tap is over 8.2. It is easily manageable. Buy many gallons of muriatic acid. You will need them as the fresh plaster further raises pH.
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Bronze Supporter
LifeTime Supporter
TFP Guide
Sep 23, 2015
Brisbane, Australia.
Geday jcolec, welcome to TFP and the forums.

Good work on testing your tap water and the TF-100, great start, your ahead of the game.

I suspect your utility manages your tap water to minimise scaling and corrosion. I think your numbers look good, better than some. If you assume a salt or TDS of around 100ppm your CSI would be -0.15. If they lowered the pH to 7.5 the CSI would be -0.85. Search your local utility for their published water quality results to see how they compare.

What the numbers mean for you though is that you can expect your TA and CH to slowly increase as you add tap water. But with rain and splash out you’ll find where your values trend. With a SWG and tap water pH of 8.2 I think your pool pH will tend to drift up but this can be managed by maintaining your TA at the lower end of the range.