Proper water balance is the single most important factor to maximizing the life and appearance of any swimming pool. The following table shows ranges for basic water chemistry.
|Total Alkalinity||80-120 ppm||Weekly|
|Calcium Hardness||200-300 ppm||Monthly|
PH is the measurement of acidity of water — measured on a scale of 0 to 14, with 7 being neutral. A pH below 7.0 means the water is very acidic; and as the pH approaches 8.0, the water becomes very basic (alkaline).
Proper pH levels are essential in order for the other chemicals to do their work. Chlorine is much less effective at higher pH levels. At a pH of 8.0, chlorine is only 22% effective.
It is also important to note that low and high levels can cause damage to a vinyl liner. Under the right circumstances, with pH below 7.0, the liner can actually grow and develop unsightly wrinkles. High pH greatly accelerates the aging process and shortens the life of the liner.
Alkalinity is a measurement of the alkaline materials dissolved in water. In the ideal range of 100 to 150ppm, alkalinity helps the pH to resist fluctuations. If the alkalinity is low, it can cause a “pH bounce” — meaning the pH level fluctuates in and out of the acceptable range.
Calcium Hardness refers to the amount of dissolved minerals in water. A low hardness can lead to corrosion of pool surface, filter, heater, ladder, ect. A calcium hardness level that is too high causes cloudy water and scaling (white chalky appearance).
Out of Balance Water
- Eye and skin irritation
- Unsightly wrinkles in vinyl liners
- Interferes with the efficiency of sanitizers
- Corrosion of metals (pump seals, heaters, lights, etc.)
- Cloudy water
- Scale build up (white chalky appearance) on pool surface as well as inside filter and heater
- Pitting and corrosion of gunite/concrete pools
Contaminants Buildup: When swimmer wastes and other contaminants build up, the result is “combined chlorine”. Shock the pool!!!
Chemical Residue: Using a calcium hypochlorite shock such as (*Shock *Sock-It *Shock-it *Burn Out *Break Out) can result in a residue build up and cloudy water. If the water looks like chalk or milk, it is usually the result of using a lot of calcium hypochlorite shock. If you use this type of shock, and want to prevent bleaching of the vinyl liner, you must:
- Fill a bucket about 1/2 full of water
- Add Shock (do not stir), let sit for a few minutes, then pour only the liquid into the pool
- Discard the residue
- Do not try to dissolve the residue
Water Out of Balance:
A high pH, high Total Alkaline or High Calcium Hardness will cause cloudy water. Test the water!!
Algae is a possible cause of cloudy water.
Is the filter system running a significant number of hours every day? During the swim season, the filter needs to run a minimum of 10 to 12 hours daily.
Pools with Cloudy Water or Algae:
- Adjust pH to 7.2-7.6
- Add algaecide
- Add shock
- Add flocking agent
- Run filter 1 hour — turn off and leave overnight
- Next day, vacuum to waste
It is not uncommon to find metals, often called free metals, dissolved in pool water. Usually, they come from source water, but sometimes come as a result of the erosion of metal pool fixtures, such as heater cores.
Free metals in pool water can cause staining of pool surfaces and inhibit the performance of water sanitizers. Ideally, there should be no metals in the water — 0 ppm. If metals are detected in your water, you will need a sequestering agent to render them harmless.
The presence of metals in the water — such as iron (reddish-brown), copper (blue-green) or manganese (brown-red) — can cause cloudiness. To remove the metals:
- Add 1 quart flocking agent
- Add 1 quart Majestic Blue
- Run filter 1 hour; turn off overnight
- Vacuum to waste
- When pool is completely clear, add a stain and scale preventer to remove any stains
Adding Water-Balance Adjustment Chemicals
It is best to pre-dissolve a water balance adjustment chemical in a plastic bucket of pool water. Then add to the deep end of the pool or in front of a return with the pump running.
pH Adjustment: Add recommended dosage, wait several hours and test water again.
Alkalinity: Add at the rate of 5 lbs or less; wait about 10 minutes between each 5 lbs.
Hardness: Add at the rate of 5 lbs. or less; wait 30 minutes between each 5. If large amounts of calcium are needed, add over several days.
|Low pH and High Alkalinity||Adjust Alk first – Next Day pH|
|High pH Low Alkalinity||Adjust pH first – Next Day Alk|
|Low pH and Low Alkalinity||Adjust pH first – Next Day Alk|
|High pH High Alkalinity||Adjust Alk first – Next Day pH|
Chlorine Stabilizer (100% Cyanuric Acid)
Stabilizer acts as a sun shield to extend the life of chlorine up to 3 1/2 times. It actually holds the useful form of chlorine in the pool water until needed, giving longer protection against bacteria and algae. It leaves no residue — 100% soluble. “Stabilized” chlorine products (sticks, tablets or chlorine powder) contain some cyanuric acid, which helps to maintain the proper level throughout the season.
With a clean swimming pool — backwash filter. Make a slurry of stabilizer and water, then add very slowly through the skimmer with the pump running continuously for at least 48 hours. Do not backwash for 3 or 4 days after adding stabilizer.
Testing The Water
- Follow test kit instructions (test strips are easier to use than kits)
- Use fresh reagents — shelf life for liquid reagents is only one year.
- Rinse out test cell with pool water before using.
- Retrieve water sample at elbow depth from deep end of the pool
Most Important Poolside Tests: Free Chlorine, pH and Total alkalinity. Free chlorine is the unused, effective chlorine that you want in your pool. With pH, a number of influences can bring out rapid shifts in the pool’s pH These include rain, swimmer wastes, refill water, and the pH of various pool chemicals, including:
- CAL HYPO – pH 11.7
- SODIUM HYPOCHLORITE – pH 13
- BROMINE TABLETS – pH 3.6
- SODIUM DRICHLORO – pH 6.0
- LITHIUM HYPOCHLORITE – pH 10.5
- CHLORINE TABLETS – pH 2.9
- CHLORINE GAS – pH 2.0
Types of Algae
Mustard Algae: Common algae in pools appears yellow-brown or “mustard” colored. It brushes off the walls of the pools easily, but quickly returns. It often grows in shady areas with poor circulation. It resists chlorine and shock treatment.
Solution: Use an algaecide along with chlorine shock. Follow label directions. Place all vacuum equipment — hose, head, pole, brushes, etc. — into pool during treatment. Maintain a higher than normal chlorine reading for 4 to 5 days after treatment.
Green Algae: Green algae is one of the most common problems for swimming pools. It usually appears in corners or other areas where circulation is poor. Once established, green algae can grow explosively.
Solution: Use Algaecide along with chlorine shock. Follow label directions. It is also recommended to use a flocking agent. Always vacuum to waste or drain (not backwash).
Black Algae: A very resistant form of algae that clings to the pool’s walls, floor and cracks. The longer black algae are present, the longer it will take to get rid of them. Black algae can actually pit the mar cite finish in a gunite pool. Treat black algae as soon as it is detected. Black algae are usually found in gunite/concrete pools.
Solution: Brush algae spots vigorously with a stiff algae brush and pour algaecide along the sides where spots are visible. Run filter continuously for one hour, and then add chlorine shock to the pool. Turn off filter and leave off for several days.
|WEEKLY||Brush walls and pool floor|
|WEEKLY||Use a maintenance dose of Algaecide|
|WEEKLY||Use a maintenance dose of Majestic Blue|
|DAILY||Maintain a proper chlorine reading|
|WEEKLY||Keep properly balanced – recommended readings:Free Chlorine:1.0-2.0, pH:7.2-7.6, Total Alkalinity:80-120ppm, Hardness:200-300ppm, Stabilizer35-60ppm|