Operating Tips

Pool Chemistry

If you treat your pool water right, your pool will treat you right, by providing endless hours of recreation, entertainment, and relaxation. While Shoreline offers carefree maintenance options, knowing the basic facts about pool maintenance can be extremely beneficial to your ownership experience. Learning about chemical storage and handling, will help ensure a safer pool experience for those who use and maintain the pool.

The chemicals needed for your pool help keep it clean and pleasant to use. But remember, these water treatment chemicals may present some hazards if not used properly. As with all chemicals read the labels and carefully follow the manufacturer's instructions. If you have any questions regarding the safe handling, storage, or use of a particular chemical, contact the product retailer or supplier.

  1. Sanitizers
    From the first day you fill your pool, the water must be maintained with a chemical sanitizer, also called a disinfectant. Enough sanitizer must be present in the water to kill bacteria and algae. Properly maintained pools normally do not have odors or cause eye irritation. In addition, you must balance your pool water to the recommended pH and alkalinity levels and you must maintain them in the proper range. For chlorine, bromine, and PHMB sanitizers, maintaining the pool water pH between 7.2 and 7.8 and the total alkalinity between 60 and 180 parts per million (ppm) will help ensure your sanitizer is effective.
    1. Chlorine
      In the pool industry, the generic word "chlorine" normally refers to any sanitizer that releases free available chlorine—also known as hypochlorous acid—when dissolved in water. Chlorine sanitizers are the most commonly used pool sanitizers. Chlorine is also a strong oxidizer.
      • Cal hypo (Calcium hypochlorite). This sanitizer is a white solid that quickly dissolves in water to produce free available chlorine. Cal hypo is available as a granular product as well as in various tablet shapes. Cal hypo has the highest chlorine content of all fast dissolving chlorine sanitizers.
      • Dichlor (Sodium dichloro-s-triazinetriones). This sanitizer is a white granular solid that quickly dissolves in water to produce free available chlorine. Dichlor contains a stabilizer that improves the chlorine stability in pool water that is exposed to sunlight. Dichlor has a minimal effect on pH and total alkalinity.
      • Sodium hypochlorite (or bleach, sometimes incorrectly called liquid chlorine). This sanitizer is a lightly colored liquid. Sodium hypochlorite has relatively low chlorine content when compared to solid chlorine sanitizers.
      • Lithium hypochlorite. This sanitizer is a white granular solid that rapidly dissolves in water to produce free available chlorine.
      • Trichlor (Trichloro-s-triazinetrione). This sanitizer is a white solid that slowly dissolves in water to produce free available chlorine. Trichlor is most commonly available in various tablet shapes. Trichlor contains a stabilizer that improves the chlorine stability in pool water that is exposed to sunlight. Trichlor has the highest chlorine content of all solid chlorine sanitizers.
    2. Bromine
      In the pool industry, the generic word "bromine" normally refers to any sanitizer that releases free available bromine—also known as hypobromous acid—when dissolved in water. Bromine is also a strong oxidizer.
      • Bromine Tablets. This sanitizer is a white solid that slowly dissolves in water to produce free available bromine. A chemical feeder is used to conveniently provide a steady addition of bromine to the pool. Chlorine and bromine can cause a fire if contaminated with combustible organic materials, such as oils, gasoline and paint thinners. These chemicals can also produce a toxic gas if contaminated with other materials.
      • PHMB (Polyhexamethylene biguanide). This sanitizer is an organic polymer liquid solution. PHMB does not release chlorine or bromine when added to water andis not compatible with chlorine and bromine. PHMB is used in conjunction with hydrogen peroxide and an algaecide.
  2. Other Supplemental Treatments
    • Ozone. Ozone is a reactive gaseous oxidizer. An oxidizer is used to destroy organic and inorganic contaminants, killing microorganisms and removing other impurities in the water. Ozone is generated and dispersed into the pool water by a device called an ozonator. Since ozone exposure to swimmers should be minimized, a primary sanitizer like bromine, chlorine, or PHMB is required to ensure that a small amount of sanitizer is maintained in the pool.
  3. Balancing Your Water's pH

    Pool owners need to test the pH level of their pool water. To test for pH, follow the instructions provided in your test kit. If the test shows that the pool water has a pH level that is too low or too high, the water must be adjusted. The ideal pH level for pool water is between 7.2 and 7.8. Remember, a high level of chlorine residual in the water can affect the pH reading.

    Pool water is too alkaline if a level of 7.8 pH or higher is detected. (The alkalinity increases as the pH level increases.) More sanitizer must then be added to maintain proper sanitation. When the pool water is too alkaline (above 7.8 pH), sanitizing chemicals cannot work properly even though the water may indicate a proper "residual" level. A scale may form on or within pool equipment, piping, and the heater coils if the water is too alkaline.

    A level that is below 7.2 pH, means the pool water is too acidic. (The acidity increases as the pH level decreases). If the pool water becomes too acidic (below 7.2 pH), the water can irritate the eyes, corrode metal pool parts and piping, and result in pool interior surface stains. It can also cause leaching in plaster pools.

    Common Chemicals that Raise and Lower pH
    Muriatic acid and sodium bisulfate are common chemicals that lower pH. Commercial strength muriatic acid, available from most pool suppliers, is about 30 percent hydrochloric acid. No more than one pint of muriatic acid should be added to every 5,000 gallons of pool water at one time to reduce alkalinity. Sodium bisulfate is an acid available in dry form and will serve the same function as muriatic acid. Soda ash (sodium carbonate) is a common chemical used to raise pH. Muriatic acid should be diluted by adding it to cold water in a plastic bucket before adding the solution to the pool water as concentrated muriatic acid is heavier than water and may sink to the bottom of the pool. Always add the diluted solution at least 12 inches from the pool wall or steps to avoid etching or discoloration of the finish. Usually the solution mixes better when poured slowly in front of an inlet fitting where the water is returning to the pool. In this way, the diluted chemical is circulated more efficiently into pool water. If there is a bottom drain in the pool, care should be taken to add muriatic acid away from the drain.

    Precautions: Always handle muriatic acid with care. If the acid spills on your hands or clothing, wash it off immediately with plenty of water. Both muriatic acid and wet sodium bisulfate are very corrosive.

    Chemicals to Control Total Alkalinity
    Pool water should also be tested for total alkalinity (basicity). Total alkalinity is a measure of the amount of alkaline chemicals or "buffering" agents in the water and refers to the degree of resistance of pH change in the pool water. Proper total alkalinity level is any level between 80 ppm and 120 ppm. If the total alkalinity is too high (above 120 ppm), the water will maintain pH at a higher level and this may cause scaling and cloudy water. Baking soda (sodium bicarbonate) is used to raise total alkalinity. Generally,an amount of 1.5 pounds of sodium bicarbonate will raise the alkalinity of 10,000 gallons of water by 10 ppm. Muriatic acid or sodium bisulfate may be used to lower alkalinity. Muriatic acid or sodium bisulfate should be diluted into a separate container of water and then added into one area of the pool (preferably in the deep end and away from walls and fixtures). The amount of acid required is traditionally referred to as "acid demand". "Acid demand" can be measured by some test kits.

    Algae Control and Algicides
    Algae are very tiny water-loving plant growths that may be introduced into the pool by wind, rain, or freshly added water. Clean-water algae may be blue-green, green, red, brown, or black in color, and can cause unusual tastes, odors, cloudiness, as well as slippery spots within the swimming area. The presence of algae in a pool will increase the sanitizer demand, and therefore, more sanitizer will be required to kill the algae. Algicides are commonly added to prevent and kill algae in the event the chlorine or bromine or biguanide residual is unexpectedly depleted.

  4. Factors Affecting the Longevity of Sanitizers
    • Swimming load. Your pool will need more sanitizer when the pool is used by large number of swimmers. Pools should be shocked or oxidized regularly during the swimming season.
    • Sunlight and water temperature. Sunlight will cause your sanitizer to dissipate more rapidly. The warmer the water, the shorter the life of your sanitizer product. This process is greatly accelerated when water temperature exceeds 85 degrees. The loss of chlorine caused by sunlight can be minimized by "stabilizing" the pool water with cyanuric acid or by using trichlor or dichlor on a daily basis.
    • Wind and rain. These elements carry dust, bacteria, algae spores, and other debris into the pool, thus consuming chemical sanitizers. This effect is increased when there are many shrubs and trees near the pool. Pool water should be shocked or oxidized after periods of heavy wind and rain.
  5. Simple Rules for Use, Storage, and Handling of Pool Chemicals
    • Establish a routine for testing and treatment. A few minutes every day—or every other day—can make the job easy and help ensure that your pool is in good working order.
    • Keep a list of emergency contact numbers readily available near the storage area for pool chemicals. In case of an emergency, dial 911.
    • Keep adequate records about pool operation, chemical purchase dates, costs, amounts used over time, as well as an up-to-date inventory of your chemicals. The pool owner should periodically review these records.
    • Keep chemicals in their original containers and ensure all lids are closed tightly when not in use.
    • Do not stack different containers on top of one another.
    • Keep all chemicals out of the reach of children.
    • Store chemicals in a cool, dry place.
    • Beware of torn, faded or illegible labels. If you don't know exactly what the chemical is or how old it is, do not use it.
    • Store pool chemicals away from other chemicals and away from equipment used for garden and lawn maintenance, such as lawn mowers, fuel and lubricants, organic pesticides, solvents, paint, and fertilizers.
    • Avoid mixing pool chemicals. Do not mix any combination of pool chemicals either accidentally or intentionally. Use clean scoops—one for each chemical—and avoid combining material between old and new containers.
    • Never pour water onto pool chemicals.
    • Enforce proper handling of chemicals. Do not inhale dust or fumes from any pool chemicals. When necessary, use proper protective devices for breathing, handling, and eye protection. Promptly wash off any residues that get on your skin.
    • Don't overdose. Measure the amounts closely. Pool chemicals—like medicine—should be used only in specified amounts. Too much can cause irritating side effects.
    • Don't guess. Take time to learn how to use a test kit. And be sure to replace chemicals in your test kit each season to ensure accuracy.

Important Pool Opening Facts

Heaters
Pool heaters have been dormant for many cold months over winter. Wiring becomes corroded, small animals may nest within and other cold weather related wear may have occured. One should expect that once the pool is Summerized and the circulatory system is active, a heater that correctly "fires up" (and is left running) by our mechanic, may stop functioning only hours later. If you have instructed us to leave your heater running at the Summerize, at your convenience please check that it is still functioning later that day or the next. If you have instructed us to leave it off, please check it in advance of any planned use as it may require unanticipated repair.

Filters/Skimmer Baskets
At time of the start of the system, your filter and skimmer baskets will be clean. Once activated, the filter cleans water that contains silt and bacteria and skimmer baskets will fill with falling debris. One must expect that filters will do their job to clarify water and skimmers will become full in as little as few hours. Should circulation diminish and filter pressure increase/decrease dramatically, a backwash service and/or basket cleaning may be required.

First Cleaning(s)
Debris and Silt from the winter season attaches to the pool finish. While initially vacuuming and brushing the pool, silt and debris become suspended and often water becomes cloudy until the filter system has its chance to clarify. One can expect that a pool will require repeated brushing and vacuuming to set the pool satisfactorily for the summer swim season.

Hydrostatic Relief Valves
Most modern pools are equipped with a safety valve at the pool floor. This valve can open and close without notice! Especially during springtime rains, the water table increases and saturates the ground around the pool. These actions will sometimes raise the water level in the pool or water can be lost as this valve attempts to re-seat itself on debris or fights continued heavy ground water pressure. This should not be construed as a defect. The valve is doing the job of saving your pool's structural integrity.

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