Cloudy or dull pool water is caused by improper chemical balance or fine debris suspended in the pool water.
Use the following steps to diagnose and resolve.
Test the swimming pool water for Combined Chlorine, pH, Alkalinity and Calcium Hardness (see how to
chemically balance your pool). The two areas most likely to cause cloudy pool water (from a basic water
chemistry standpoint) are pH and Calcium Hardness.
If the pool chemical levels are not within the following suggested ranges, adjust the chemicals and run the
pool filter system for 12-24 hours before re-testing. Free Chlorine: 1-3 ppm (Total Chlorine level must be the
same as the Free Chlorine, if the Total is higher, there exists Combined Chlorine's or Chloramines). Combined
Chlorine should be ZERO), PH: 7.2 – 7.4, Total Alkalinity: 90 – 120 ppm and Calcium Hardness: 200 – 350
If you are unable to maintain a solid chlorine level for at least 3 consecutive days without shocking, you
may have a chlorine demand problem which will require special treatment & needs to be addressed before the
If all the pool chemical levels test in range, the cloudy pool water is caused by fine debris suspended in
the pool water. You should backwash or clean your pool filter following the manufacturer’s instructions, and
run the pool filter system continuously for 24 to 48 hours.
If the water conditions have not significantly improved you should add a clarifier (see below) chemical
to the water to help your pool filter remove the fine debris from the water. Continue filtering until the
water clears. Often a pool can be too cloudy for a clarifier. Then move up to a floc. This will
drop suspended particles to the floor. Then vacuum it to waste.