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Free Chloride Too High But Total Chlorine Fine?


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New pool owner... small 5,000 gallon above ground pool. Today's test redings... Hardness- 0 Total Chloride- 3 Free Chlorine- 10 (as high as my test reads) Bromime- 20 ( also as high as my test reads) Ph- 7.2 Total Alkalinity- 40 CYA/Stabilizer- 50

Help! I didn't think it was possible for my free chlorine to be higher than my total chlorine. . It's been reading like this for over a week now! Yesterday, I replaced my filter and backwashed some of the water out and refilled it with fresh water to hopefully bring down the levels some but obviously it didn't work. The pool stays uncovered and I've read that the sunlight will eventually break it down but no luck there. I use a chlorinator floater set for the gallons of water in the pool and I haven't shocked in over two weeks. What am I doing wrong here? How can I fix it? And is my pool safe to swim in?

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It is possible if your your TC is very high. It can bleach out some chlorine tests and give you a lower reading than it really is. TC often is higher than FC if there are water chemistry problems and the fact that the FC test is off scale makes the possiblity of bleachout likely.

As Dr. Spa asked, how are you testing?

A few observations, Even though there are scales for bromine and chlorine you only read the scale for the santizer you are actually using.

It's not total chloride, it's total chlorine.

If you want to bring the chlorine level down then take out the floater until the level drops. It is putting too much chlorine in the water.

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Aquachem test strips. And the Total Chlorine level is 3 with the Free Chlorine level is 10. How is that even possible? I read that the Total Chlorine level is the combination of the free chlorine and the chlorine you add... I would understand a bleach out if my total was higher than my free but wouldn't it bleach out the total chlorine reading too if it was that high? Sorry about the typo's, not used to my smarty pants phone yet.

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Your drop based kit uses OTO which only tests total chlorine.


so if your FC is over 10 ppm and you have CC (combined chlorine) in addition to the FC it is entirely possible for the TC to be high enough to bleach out. You could also have bad strips (NOT an uncommon occurance!)

Test strips are useless, btw. Aquachem's parent company, Chemtura, used to offer a drop based kit under the Aquachem brand (they have severel brands besides AqauChem--Bioguard, Sun, Omni, Simplicity, Guardex, PoolTime, Spa Time, SpaGuard, SoftSwim/SoftSoak just to name a few of their N. American brands!) but discontinued it Having good test results would most likely hurt their bottom line because pool owners would not need all the unnecessary chemicals they sell if the pool was kept properly balanced in the first place.

My recommendation to you is to get a Taylor K-2006 test kit. Your wlll probably have to order it online since it is not stocked locally by most pool stores. It will be the best investment you can make into the care of your pool and it will save you a lot of money in the long haul. It will test FC and CC up to about 50 ppm with a precison as great as .2 ppm and it is not a color matchng test, it is a drop counting (titration) test with a color change from red to colorless. The Total alkalinity and calcium hardness tests are also drop count tests with a precision of 10 ppm. Strips cannot measure calcum hardness, they measure total hardness which is a useless test for pool water balancing and have a precision of +/- 40 ppm on the TA test, which is useless for water balancing. The TA test is a turbitity test (disappearing black dot test). Strips are notorious for bogus CYA measurements! pH test is high precision with acid and base demand tests which are useful when pH is out of range or when you want ot know exactly how much of a chemical you need to move your pH to a desired target.

Hope this is helpful.

The Taylor website has videos of the testkit in action so you can see how easy it is to use.


Click on the link in the upper left that says Pool/Spa and the scroll down to view the videos for the K-2006 . The K-2005 is almost identical but the chlorine tests are color matching tests, suffer from bleachout at high santizer levels, and require a complicated dilution procedure to test chlorine levels over 5 ppm which is why the K-2006 is the better test kit. All other tests in the two kits are identical.

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