Chlorine Demand Trouble Shooting Instructions

What is a chlorine demand and how do you know if you have one? A chlorine demand is the difference between the amount of chlorine added to the water (total chlorine) and the residual amount of chlorine after a given amount of time (free chlorine.) Usually your total and free chlorine numbers will be matching. If they are more then 1.5 in difference and your water is going a bit cloudy, you have a chlorine demand.

There are many reasons why a chlorine demand can occur. .There can be excessive nitrates, ammonia compounds or simply a build up or organic materials that have remained oxidized for a period of time.

Before you being:
1. Ensure that your jets are facing down at a 45 degree angle to circulate the pool properly.
2. Has your filter been chemically cleaned and its in good working order? Even if your filter was chemically cleaned a few weeks ago, all it takes are some seeds of pollen to be in the filter decomposing to create a chlorine demand.
3. Fill your skimmer basket with sticks. If you have a salt pool, turn your power level and output to maximum

If the pool is cloudy, we can try to clear the pool faster by adding Pool Tonic and Polysheen directly to the pool.

Part A: Oxidation (Note: you only use one of these options)

1. Burn Out 3. Tonight, when the sun is off the pool, broadcast Burn Out 3 slowly and evenly around the deep end of the pool. (TIP premix if your water is not up to swimming temperature.) Brush the sides and the bottom of the pool.

2. Ultra Shock. Broadcast Ultra Shock slowly and evenly around the deep end of the pool. Brush the sides and the bottom of the pool.

3. Power Chlor. Remove your skimmer basket. SLOWLY AND WE MEAN SLOWLY pour Power Chlor into the empty skimmer. This should take about 15 minutes to do.  Pu the basket back in and brush the sides and bottom of the pool.

Caution: When chemicals are not fully dissolved or is applied too quickly, permanent staining can occur.

Part B.

Wait 2 hours and test the free chlorine reading. If the level is 5 ppm or above, continue circulation for another 12 hours and retest. If the level stays above 5 ppm for a 24 hour period, there is no  longer chlorine demand for your pool.

If at any time during the 24 hour period the chlorine level is reading below 3 ppm, apply another oxidation treatment or, bring in a water sample and ask for a chlorine demand test. This test is a special diagnostic tool that takes us to 48 hours that can determine the full dose of oxidizer required to satisfy the chlorine demand in the pool.

If you have any questions please email us at

-Keep your pool circulating on ‘filter’ for 24 hours per day for all these procedures.
-Fill your skimmer basket with chlorine sticks
-Ensure that you leave your solar cover off until the chlorine level is 3 ppm or less.
-Partially drain the pool so that only 6″ of water is remaining in the shallow end (subject to season ground conditions) if you feel this will be a more cost effective treatment.


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