I added a bit too much chlorine & the level went up to 31 PPM, I checked it in the morning & it was at 32 PPM? I didn’t add anymore chlorine & the following night’s reading was 18 PPM, which was closer to what I was aiming for, with the morning reading at 19 PPM. The next night the reading was 10 PPM with the morning reading at 11 PPM! The CYA is at 42, the pool had a small amount of green algae I could not get to go away so I figured I would do the SLAM! I’m confused as to how or why the chlorine level would go up by 1 PPM overnight, do I need to keep adding chlorine or let the levels come down to normal?
Overnight chlorine goes up overnight
- Thread starter dave2spd
- Start date
The $1100 photometer is +/- 25% up to 15 ppm.
Yours is no better, and likely worse or the pool stores wouldn't be spending $1100 on their machine.
Test Kits Compared
Yours is no better, and likely worse or the pool stores wouldn't be spending $1100 on their machine.
Test Kits Compared
- Jun 24, 2021
- 16,171
- Pool Size
- 29000
- Surface
- Vinyl
- Chlorine
- Salt Water Generator
- SWG Type
- CircuPool RJ-60 Plus
Here are the kits we recommend and comparison of accuracy...Link-->Test Kits Compared
We don't trust the photometric test kits, there are notoriously wrong. Making recommendations from them, we can do more harm than good.
I found their specs in the manual and they only rate it to 8 FC, which is your 1ppm you are off. (They assume perfect conditions and calibration, of course)
Can I get an educated guess to my question? I did remember seeing another test kit when I moved in, it is a Taylor but the reagents are all > 3 years old!
+/- 1 ppm at 4??? That's awful.
That leads to a good question though: @dave2spd how many gallons did you add before getting your 32 ppm reading?
I was using 1/10 of pool water, 9 parts distilled & multiplying by 10 to get the reading!
Ok... Why were you adding 44 ppm worth of chlorine if your CYA is reading at 40-ish?
Standard issue +/- 25% like the pool store. I'm shocked they claim the accuracy improves as the FC increases, though its just a claim.
In a backyard, at 'it came with the house' years old.........
Anywho @dave2spd. Time for a reliable test kit. Either option at tftestkits.net is a better value than their Taylor counterpart, using the same Taylor reagents. Or spend the same for less and buy a k2006 or k2006C.
Check the link I posted above.
It's a one time purchase and the refills once you have all the parts needed are mid $50s. They even go on sale each spring for mid $40s.
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Just to drive it home: even if you managed to get an absolutely perfect 10:1 ratio the reading of 3.2 you got is still +/- 0.75. That means an extrapolated reading of 32 is anything from 24.5 to 39.5. Again, that is the best possible margin of error only possible if the samples were measured out absolutely perfectly.
Added the same day, not all at once, I got the chlorine level to 15ppm with 6 gallons then it seemed to start to drop. I may have not tested the level correctly thus over chlorinating! So I need to get the better test kit! Is there any chance of saving this SLAM? It seems I’m not getting a loss of chlorine overnight & the pool is looking good just a little cloudy, getting better each day!
You don't waste your time on the OCLT until you have How Clear is TFP Clear? water.
Have a refresher :
SLAM Process
And again so you don't have to scroll back up
: Test Kits Compared
Ordered!You don't waste your time on the OCLT until you have How Clear is TFP Clear? water.
Have a refresher :
SLAM Process
And again so you don't have to scroll back up
Test Kits Compared