testing FC with K1001 is 5PPM but with K2006 ( 0870-0871) is 18 PPM, CYA 35

ste

Active member
Apr 25, 2019
41
costarica
i tested FC for 1 month with K1001 and the color result was always around 5ppm, but when i finally could buy new R-0870 and the big bottle of R-0871 , i added water to 10 ml mark and put 1 big dipper of 0870 and than i had to add 36 drops of R-0871 to get colorless ,doing the math i get 18 ppm ,how is that possible?
 

ajw22

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TFP Guide
Jul 21, 2013
21,190
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
That is why we say that the K1001 is only good for telling you if you have chlorine or not.

If you did the test properly with the bottle vertical and letting the drops form and fall off the tip then trust the FAS/DPD test.

BTW, your subject line says 1 PPM and your post says 18 PPM. Edit your subject line to not confuse folks.

 

ste

Active member
Apr 25, 2019
41
costarica
i tested FC for 1 month with K1001 and the color result was always around 5ppm, but when i finally could buy new R-0870 and the big bottle of R-0871 , i added water to 10 ml mark and put 1 big dipper of 0870 and than i had to add 36 drops of R-0871 to get colorless ,doing the math i get 18 ppm ,how is that possible?
That is why we say that the K1001 is only good for telling you if you have chlorine or not.

If you did the test properly with the bottle vertical and letting the drops form and fall off the tip then trust the FAS/DPD test.

BTW, your subject line says 1 PPM and your post says 18 PPM. Edit your subject line to not confuse
Sorry i tested with k1001 and got 5ppm but with k2006 i got 18ppm
 

ste

Active member
Apr 25, 2019
41
costarica
Ok i try to explain it better ,i was not at home for 1 month and my wife test the pool with k1001 and added about 400 ml of liquid bleach at 12% every day to keep the level above 5ppm ,now i'm back and i bought 0870 and 0871 brand new .... i tested water with k1001 and the color was around 5 ppm , but than when i tested with k2006 i had 18 ppm how is it possible ?
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
21,190
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
400 ml of 12% LC in your 20,000 liter pool was adding 2.5 ppm of FC every day.

If your daily FC consumption was 1.9 ppm per day and you had an excess of 0.6 ppm FC building in your pool then over 30 days it would accumulate to 18 ppm.

It is not a big problem. Just a bit above SLAM FC level for CYA 40. Now that you have a good test kit let the FC drift down around 7 and then add 300 ml/day to add 1.9 ppm of CL and keep your FC around 7.
 

ajw22

Gold Supporter
TFP Guide
Jul 21, 2013
21,190
Northern NJ
Pool Size
35000
Surface
Plaster
Chlorine
Salt Water Generator
SWG Type
Pentair Intellichlor IC-60
Rain and clouds would reduce the chlorine loss due to the sun UV. When it is cloudy or raining your pool needs less chlorine added. You need more LC on sunny days.
 

HermanTX

Gold Supporter
May 20, 2020
972
Katy TX
Pool Size
14600
Surface
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Chlorine
Liquid Chlorine
Ok i try to explain it better ,i was not at home for 1 month and my wife test the pool with k1001 and added about 400 ml of liquid bleach at 12% every day to keep the level above 5ppm ,now i'm back and i bought 0870 and 0871 brand new .... i tested water with k1001 and the color was around 5 ppm , but than when i tested with k2006 i had 18 ppm how is it possible ?
The K1001 is good to maximum of 5ppm. There is no scale above that. This is why it is recommended to use the FAS/DPD test which is valid for high levels of chlorine. As indicated by others, the yellow tells you that you have chlorine and if it is at dark yellow it is greater than 5ppm. If it is clear to light yellow it may register on the scale from 1 to 5 on the K1001 kit.
 

Oly

Gold Supporter
Jun 28, 2017
1,693
Fresno, CA
Daily FC loss is a moving target. Mid winter and mid summer losses tend to be the more consistent but during the spring and fall all bets are off and FC demand can change quickly. The fires here in CA produced so much smoke that my FC loss dropped by over 50% for almost two weeks due to the reduction in solar radiation. Testing more frequently with a FAS-DPD kit will help track your pool systems sanitation requirement. You did err to to high side so you have that going for you. :cheers: