Today’s question came to us from a frustrated (and annoyed) mother who recently learned that her kids took the liberty of adding chlorine to the pool… in an effort to help get rid of the dirt in the bottom!
“Hello and let me tell you that i’m pretty mad right now at my teenage boys who i thought knew better, but i guess really don’t. I got home from work last night to find my twqo boys age 10 and 12 out by the pool with two garden shovels and the bucket of chlorine dumping scoop after scoop into the water! They wanted to get rid of some DIRT they saw in the bottom! Ugh! I stopped them but it was too late. Half the bucket was GONE! At $60 a bucket best believe money for a new one will come out of their allowances, but how can I find out how much chlorine is in the water? My test kit turns CLEAR which means no chlorine but I know thats not true because I can SMELL the stuff from inside the house! Is there a kit that can help? Thanks”
Before we get into the matter of how to test for and deal with the chlorine issue we want to stress the importance of keeping all pool chemicals out of the hands of children. Granted this woman’s children probably knew better than to eat the chlorine but it still posed a danger to their breathing, skin and eyes.
Some compounds frequently found in pool sheds like the hydrogen peroxide sold for use in pools using a biguanide sanitizer system, liquid chlorine, and muriatic acid can cause immediate skin irritation and damage to pretty much anything they touch.
Keep all pool chemicals locked away and out of the reach of those who have no business messing with them!
Why is her chlorine test kit not working?
From the sounds of things her mischievous children added WAY too much chlorine to the water and the super high chlorine level basically bleached out the chlorine indicator.
As an example of what we mean, DPD test reagents for chlorine testing get annihilated and become useless in the presence of around 9 or 10 ppm chlorine.
Dilution method for high range chlorine testing
To avoid purchasing additional testing products one could always practice dilutions of samples and repeated testing of the diluted mixtures until the testing method used no longer gets bleached out by the chlorine.
Example: Performing chlorine testing on a mixture containing 50% distilled (or otherwise oxidizer free) water and 50% pool water that contains 12 ppm chlorine should yield test results of 6ppm. One would then double the test results to get the true chlorine concentration of the pool water sample.
Simplest method for high range chlorine testing
While DPD and OTO will get bleached out by elevated levels of chlorine in a water sample, the reagents used by the WaterWorks High Range Free Chlorine Test Strips and WaterWorks High Range Total Chlorine Test Strips will not.
- High Range Free Chlorine Test Strips detection range: 0 ppm – 120 ppm free chlorine
- High Range Total Chlorine Test Strips detection range: 0 ppm – 80 ppm free chlorine
Getting chlorine levels down fast
More than likely someone would want to reduce the chlorine levels since elevated chlorine levels in a swimming pool make the water unsafe for swimming and potentially damaging to pool equipment… as well as quite smelly as our reader pointed out in her inquiry earlier.
Otherwise just the passing of time (and exposure to biological contaminants coming from the air) should cause chlorine levels to drop back down to normal ranges.