How To Test Swimming Pool Water
Water Chemistry is a term used to talk about all the different chemical products available to the swimming pool industry.
How chlorine kills bacteria and sanitizes the water as well as the discussion of acids and pH levels is considered
chemistry. Water Balance is a state when these levels of chemicals are safe to swim in. When a level is "out of
balance", we have to use chemistry to return the water to safe conditions.
This is a measurement from 0-14 of how acidic or alkaline (basic) your water is. The proper pH range for a swimming
pool is 7.2-7.8. The lower the number, the more acidic the water is which will corrode metal and equipment, cloud the
water, and cause swimmer irritation. Readings above 7.8 will cloud the water and cause swimmer irritation as well as
increase the risk for algae, scale, and filtration problems. The ability of chlorine to sanitize the water is affected when
pH is out of proper balance.
This is a reading that is important because it shows how stable the pH level is. The Total Alkalinity keeps the pH level
from fluctuating all the time and depending on your type of pool and what part of the country you live in, the reading
should be between 80-150ppm.
Total or Calcium Hardness
This reading determines how "hard" your water is due to calcium and other minerals. The reading range should be
between 200-400ppm. You can add chemicals to make your water harder, but not if the reading is too high, you would
need to drain water out of your pool
Free Available Chlorine
This is an important reading because it shows the amount of chlorine that is available to clean and sanitize the water.
The range should be between 1.0-3.0ppm.
This refers to chlorine molecules that have attached to some kind of containment such as soap, ammonia, or another
organic compound. High levels of combined chlorine can cause a foul odor, and you should shock the pool if you have
a level above 0.2ppm.
The amount of "Free Available Chlorine" + "Combined Chlorine"
Total Dissolved Solids
This measurement shows us the amount of dissolved solids such as dirt, waste, chemicals, etc in the water. This
reading should not exceed 1500ppm; if it does, you need to drain water and add fresh water to the pool.
Cyanuric Acid or Stabilizer
UV rays cause the effectiveness of chlorine to fall rapidly. Cyanuric acid helps prevent this from happening. A good
level for this is 50ppm.