Can't Get Your Chlorine to Register?

A common problem when you first open the pool in the Spring is balancing your pool water chemistry. Every year I see some issue that will ring as a common theme. Last year for example lots of green pools with low PH and Alkaline levels which correlates with the wet, rainy Spring and Summer season we had. This year promises to be much improved where we may actually go swimming for a change, but I am testing a lot of pools with higher levels of PH and Alkaline at opening time “hmmm” unusual in my experience but we are dealing with it by using PH down when appropriate.

I am also getting a lot of people in the store with no chlorine reading at all, first I will test with the computer using my strips but sometimes there may be chlorine there but it is bleaching the pads on the test strip so I will then do a drop test, most times there will be some chlorine when I do this test. However, when there seems to be a chlorine lock, that is when there is no free chlorine showing there is something amiss in the water chemistry we need to address either by super chlorinating, or testing for other issues such as nitrates or most common in my particular area phosphates. Now, I was always told that phosphates appeared if you had recently fertilized your lawn, so for years we never tested for phosphates on a regular basis, but there are several ways your pool can become contaminated, fertilizers just being one. Municipalities also use phosphates to clean the water pipes your city water goes through and in our town we have a water tower for one neighborhood which can also be cleaned with phosphate containing materials. Even some chemicals used to take metals out of our pools can contain some phosphates so all these factors add to the list of why your chlorine is being digested too quickly to do its true job of sanitizing your pool. If phosphates are tested for and you have a high level then the fix can be an easy one usually with a treatment of a chemical that removes the phosphates from the pool and you need to follow the instructions of the label to a tee.

As an aside to this, some will say well you can dump half the pool and refill and dilute the phosphates out but let’s think this through first. If you think you ended up with the problem because the phosphates are in your water source this will not be the best idea as you will only be repeating the cycle, if you have well water, again, you will need to treat with a sequestering chemical to get the metals out so that’s not a good idea either so most times the Phosphate chemical treatment will be the route to take.

As a refresher, free available chlorine is that portion of chlorine that is capable of oxidizing contaminants where as total chlorine residual is the combination of free chlorine and any combined chloramines. Chloramines are weak cleaners because the chlorine is locked with ammonia and is not available to kill bacteria (chlorine lock). The ammonia comes from human sweat, urine and when there is insufficient chlorine present to combine with all the available ammonia and to oxidize bacteria. One active swimmer in your pool for an hour produces one quart of sweat per hour. So you may have a test reading total chlorine with no free chlorine and therefore available chlorine is locked.

A myth is that you have plenty of chlorine or high chlorine levels if you smell the odor or have irritated eyes but these are actually signs of chloramines not too much chlorine. In order to neutralize chloramines super chlorination is suggested and there are various methods used with some suggesting up to 8 gallons of liquid chlorine for 20K gallons of pool water circulating the water until the levels read normal. I would suggest no swimming at this treatment time till levels come down.

Lastly, a quick note on chemical storage and safety. Keep your chemicals in a cool dry place with containers labeled. Don’t stack one type of chemical on top of the other in case of a spill and never consolidate a chemical into another container not specifically meant for that chemical. My personal advice is to purchase what you need when you need it, as an example, liquid shock comes packaged with vapor caps and can lose its concentration quite quickly so storing it is wasting your valuable dollars.

We are looking good for a long hot summer season folks so stay safe, think before you act, watch those kids always and Don’t Drink and Dive.

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