How to Treat Cistern Drinking Water With Pool Chlorine

Using pool chlorine to disinfect water from a cistern is an easy way to make safe drinking water. This is especially true if the cistern collects rain water because rain water is already fairly clean. The best form of pool chlorine for disinfecting drinking water is granulated calcium hypochlorite, a solid chemical. This form is optimal because it is easy to work with and spills are easy to clean up. Using a liquid form of pool chlorine is much more difficult and dangerous and is not advisable.

Things You'll Need

• Two capped containers
• Granular calcium hypochlorite
• Measuring spoon

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Instructions

• 1

  Mix 1/8 oz. granular calcium hypochlorite per gallon of water in one of the containers. Calcium hypochlorite contains about 70 percent available chlorine by weight, making this mixture about a 500 mg/L chlorine solution. You will now have a stock chlorine solution for disinfecting drinking water.

• 2

  Mix the stock chlorine solution with the water to be disinfected in a different container at a 1 to 100 ratio. This is about equal to 6.5 oz. of chlorine solution for every five gallons of water you are disinfecting.

• 3

  Make the container safe to pour or drink from by loosening the cap enough to let a small amount of water out and turning the container upside down. Make sure the chlorinated water drips out and coats all of the threads or indentations on both the container and the cap. Let the water sit for at least 30 minutes before drinking.