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Why would my pool water be green?
Last Updated: 08/13/2010
Why is my pool water green?
 
If your pool water is green you have algae.
 
To address this issue, you must first look at why the pool turned green.
  • Test your pool water.  Preferrably testing the Total Dissolved Solids as well as the Phosphate levels as well as your normal Free Chlorine, pH, Total Alkalinity, Calcium, stabilizer and Combined Chlorine readings.
  • Is your pool filtration system operating long enough every day?
  • Is your pool filter in good working order?
  • Is your pool pump moving water?
After making those assessments you must make adjustments.
  • Address the filtration system first. 
    • Make any needed repairs to the pump and filter.
    • Set the pump to run for 24 hours a day until the pool is cleared.
  • If your stabilizer is too high, greater than 40 ppm, or you have too many Total Dissolved Solids, The best thing for you to do next is to lower the water level in the pool and add fresh water to dilute both.
  • Recheck your pool chemical balance and adjust as needed.
    • Add the appropriate amount of Phosphate Remover.
    • Balance the Total Alkalinity
    • Balance the Stabilizer to 40 ppm.
  • Super-Chlorinate the pool.
  • Brush the pool walls and floor.
  • Repeat until the pool has cleared up.
Occasionally you will find a pool that will not clear up.  If this is the case you may need to Floc the pool.  This is a chemical added to the pool water that will take the smaller floating particles that make the pool cloudy, combine them to each other and drop them out of suspension in the water.  Follow the manufacturer's instructions.
 
If you are using an algaecide treatment to clear your pool, follow that manufacturer's instructions as you may need to add the algaecide before super chlorinating.
 
If the pool has been stagnant for an extended period of time you may need to take more drastic measures to clear the pool.  You may need to drain and chemical was the pool surface.  If this is the case, you are best off getting the help of a pool professional as some pools have to be treated very carefully when draining to prevent hydrostatic lifting.


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