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How to test for chlorine in freshwater with Taylor test strips

What is it? Chlorine, on its own, is a greenish-yellow, highly reactive and diatomic gas that is almost never found free in nature by itself. When found in freshwater, chlorine is most often found bonded to other elements and ions.

Why is it important? We use chlorine to disinfect public water supplies from pathogens, such as bacteria and viruses. Chlorine acts as an important part of the cleaning process to ensure a healthy drinking water supply in cities. Chlorine is used in water treatment plants, our water distribution systems, in supply reservoirs, including cisterns. It follows that we sometimes find leftover traces of chlorine from water treatment in our freshwater systems including lakes, rivers, and streams.

What does it mean? Remember — all the water that comes out of your tap, as well as down your drain, comes from a water source and eventually finds its way back. You likely will only find small traces of chlorine in most freshwater systems. If you read your test results and note levels of chlorine in your water, you may be near a water treatment plant, or close to someone dumping pool water. Runoff from common domestic water uses, such as watering gardens, car washing, swimming pool draining, and driveway or road flushing, can all carry chlorine some distance, and end up in our lakes, rivers, and streams.

Learn more

How to test

Taylor teststrips are part of a number of Water Rangers' testkits. They measure pH, chlorine, alkalinity and hardness.

  • Rinse sample cup 3 times.
  • Shake out 1 test strip, close bottle. IMPORTANT! Make sure your hands are dry, since moisture in the container will ruin strips.
  • Dip the entire strip in the water in the sample cup. Remove after 2 seconds.
  • Wait 20 seconds before reading results.
  • Compare colours with guide on side of bottle. Line up the colour strips vertically so that you can compare along the spectrum for each value.

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