Odd pre-pre-preseason pool measurements

Soupy

LifeTime Supporter
Jun 23, 2011
158
Maryland
I just grabbed a small sample of pool water and measured the following:
FC 0
pH 7.2
TA 20
CH 50
Salt below the scale on the test strips, maybe between 0 and 200.
Borates 10
Temp 47F (measured on my water sample after I brought it back into the house, so the actual pool could be a few degrees colder)
CYA 0

My last measurements from September 2020 were:
FC 6.0
CC 0
pH 8
TA 110
CH 260
Salt 3140
Borates 35
Temp 80F
And I apparently forgot to log CYA late in the season, but it was 60 in July.

What I really don't understand is how TA, CH, and Salt are so low. My closing process involves draining a good bit of water, and the pool has already refilled itself with rain/snow, so I know there's some dilution. But that can't remotely explain salt dropping to nothing.

Are the tests inaccurate if the water is too cold? Should I warm it up to room temp and then test?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
24,960
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Is your pump running?

Without your pump running the water stratifies and you can't get accurate chemistry.
 
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Newdude

Gold Supporter
TFP Guide
Jun 16, 2019
6,960
NY
+1. I saw huge differences between that first test and the test after 2 days of pump running.
 
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JamesW

TFP Expert
Mar 2, 2011
24,187
Most of the water on top is rain and snow.

Full mixing will reveal the real numbers.
 

Newdude

Gold Supporter
TFP Guide
Jun 16, 2019
6,960
NY
According to NOAA you got about 2 ft of rain from Oct through Feb. Your CH and salt probably decreased by 1/3. Your CYA lost the same 1/3, (down to 40) and also 3-5ppm a month in normal degradation, so CYA is 20 at best and unmeasurable if less than that.
 
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Soupy

LifeTime Supporter
Jun 23, 2011
158
Maryland
Yeah, the pump isn't on yet. A lack of mixing makes sense. I've got a small submersible pump, could throw that in without a hose on it and let it stir things up.
 
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ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
24,960
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Don't bother. Just relax until you open your pool.
 
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