Following are some of the basics of pool chemistry. 

For specific quantities of which products to add to your pool, or for specific problems, we strongly suggest having your water tested by a a pool professional in the spring and periodically throughout the season. 

  • Calcium
    200-400 ppm
Often overlooked, hardness levels play a role in balancing water and can also determine how effective your sanitizer works.  Soft water is not recommended in a pool, since it is very corrosive to pool surfaces and equipment, while excessively hard water leads to calcium deposits on surfaces and equipment.  Raised by adding calcium carbonate or lowered by partially draining and refilling pool water to reach the correct balance.
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  • Alkalinity
    80-120 ppm
The pH of pool water will fluctuate, unless the alkalinity is within the desired range.  It is recommended to check alkalinity every other week.  Alkalinity is lowered by Muriatic Acid or raised by Sodium Bi Carbonate.  Always make adjustments gradually so you don't over shoot your ideal range.

  •  pH
      7.2 - 7.6

The single most important parameter of healthy pool water is pH. Recommended level are 7.2 - 7.6. pH is lowered by adding muriatic/dry acid and is raised by sodium carbonate. High pH levels can result in cloudy water and render chlorine ineffective. Low pH levels can be irritating to swimmers as well as cause damage to pumps, heaters, and equipment.



  • Chlorine
    2-4 ppm for pool
    3-8 ppm for spa
The most widely used sanitizers are liquid Sodium Hypo, Trichlor, Dichlor, Calcium Hypo, Lithium Hypo, and Chlorine Gas.  For the homeowner, liquid Trichlor and Calcium Hypo are commonly used.  For outdoor pools, Trichlor has the advantage of a built in stabilizer (Cyanuric Acid) to help the chlorine not dissipate by the sun as fast.  Always apply Trichlor through an automatic feeder or floater.  Putting Trichlor into a skimmer can cause premature plumbing damage to equipment and heater failure since it is very acidic.  Liquid chlorine is effective for daily chlorination, however, it can be difficult to transport.  It is also necessary to shock the pool to oxidize organics, rejuvenate the chlorine, and prevent algae.  Shocking is done periodically, depending on air temp, weather, and bather load.  Generally for homeowners, one pound of Calcium Hypo per 10,000 gal of water, or one gallon of liquid per 10,000 gal of water, is sufficient.  This should be done around dusk, closing the pool to bathers until the chlorine levels return to ideal levels.  Non-chlorine shock is also an alternative to chlorine based products, which allows bathers back in the water in around an hour.

  • Chlorine Testing
Always use a test kit that reads both free and total chlorine levels.  Free chlorine is an effective sanitizer, but as it breaks down, it becomes combined or chloramines.  This will give off an offensive chlorine smell, irritate eyes, and use up the rest of your free chlorine.  Total equals free cl + comb cl so subtracting free from total would give you your combined reading.  Anytime there is more than .4 combined the pool should be shocked.

  • Cyanuric Acid (stabilizer)
    20-40 ppm
Stabilizer is used to help outdoor pools maintain chlorine levels by slowing down chlorine dissipation by the sun.  If you use a stabilized chlorine product, your levels will increase gradually so there is no need to add additional stabilizer.  If you're using only liquid, you should probably add the recommended amount of granular stabilizer.


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