The most common chemical that is used to kill bacteria, living organisms and any other contaminates (such as dirt, debris, and algae spores) that are in pool water. The two most common forms of chlorine are Dichlor (60% granular chlorine) and chlorine tablets called Trichlor. Chlorine tablets may come in Triplex form with the addition of a small amount of algaecide and Flocculants.



An "as-needed" chemical. If algae does occur, Algaecides are used to help kill algae. The majority of algaecides are liquid, but some types do come in granular form. Once you determine the type of algae (green algae, mustard algae, or black algae), you can purchase the appropriate algaecide and begin the proper treatment. Then read the instructions on the label to determine the amount to add, how it should be added (most manufacturers of algaecides recommend pouring it straight from the bottle), and other precautions. Note: In conjunction with the algaecide, you will also need to use a chlorine-based shock and engage in a labor-intensive and time-consuming maintenance schedule to eliminate the algae.



Also called Clarifier: An "as-needed" chemical. If water is cloudy, it may be due to thousands of small particles (bacteria, dirt, and other debris) that are suspended in the pool water. These particles are so small that they escape both the chemicals and the filter. If this is the case, a Clarifier is used to restore water clarity. Clarifiers are liquid. Read the instructions on the label to determine the amount to add, how it should be added (either diluted in water or poured straight from the bottle), and if it should be added before or after shocking the pool; clarifiers are often used in conjunction with shock to restore water clarity.



This is relative acidity or alkalinity of water. The pH scale ranges from 0-14 with 7 being neutral.A pH level of 7,2 – 7,6 is ideal for pools.


High pH will lead to the following problems:


  • - Cloudy water.
  • - Scale formation on the water line, the pool walls, floor, plumbing and equipment.
  • - Minimizes the effectiveness of chlorine and other chemicals. High pH will also cause the use of more chlorine with poor results.
  • - Algae growth.
  • - Eye and skin irritation.

    Low pH will lead to the following problems:


  • - Disintegrates metallic parts of your pool (ladders, hand rails, light fixtures, and equipment). This could even lead to discolored water or stains on the pool walls and floor.
  • - Stained and etched concrete in concrete pools.
  • - Stained, etched and delaminated internal surface in Hydrazzo pools.
  • - Stained and etched of tiles and grouting in tiled swimming pools.
  • - Stained liner in vinyl-liner pools.
  • - Minimizes the effectiveness of chlorine and other chemicals.
  • - Eye and skin irritation


    Lowering pH

    pH drops with the use of Dry Acid (also labeled Sodium Bisulphate).The amount to use depends on the level required to correct and the pool volume.Use 2 kg of Dry Acid to lower the pH from 7,8 to 7.4 in 100 tons of water.If pH is higher than 8,0 it is recommended to add a maximum of 3 kg of acid per 100 tons of water and test again in 48 hours.Dry acid must be entered in the pool diluted in water and dropped as a solution directly into the pool deep side.Do not drop undiluted acid in skimmers or to the pool as it cause considerable damage.



    Raising pH

    pH drops with the use of Soda Ash also labeled Sodium Carbonate.Use 2 Kg of Soda Ash to raise the pH from 6,8 to 7,4 in 100 tons of water.Do not use more than 3 Kg of Soda per 100 tons of water and test again in 48 hours.




    A test kit is the right way to check a pool’s water quality.

    Water test for Chlorine, pH and Total Alkalinity


    1.Rinse well the Test Kit container.

    2.Fill the Test Kit container with10 ml pool water

    3.Add 5 drops of OTO (yellow top) tester which is mark CL

    4.Add 5 drops of THENOL (red top) tester which is mark PH

    5.Plug the containers with the container cups

    6.Stir gently 2 -3 times the Tester

    7.Match the colours in the containers with the colours next to them.

    8.According to your reading dissolve the quantity require in a bucket with water. Dissolve the chemical well (pump must be on when chemicals are added in the pool). Both products Chlorine & Ph- (dry acid) must be added directly into the swimming pool.

    9.Chlorine and pH- (dry acid) should be mix separately and not at the same time when dilute.

    10.If the pump is on timer and the chemicals are added at a time that the timer will stop the function of the pump, put the pump on manual for at list 2 hours.



    Water is often characterized Hard or Soft depending on the content of Calcium or Magnesium Salts.Hard water contains a high level of salts and will cause sediment on the pool surfaces especially the water line.Soft water will cause problems in pools as it will have a calcium demand and will seek calcium from the pool structure (grouting, plaster surface material).The advisable level is 200 – 400 mg/l.Calcium Chloride can be added to the pool water to raise the level of Calcium Hardness.Dilution (adding of fresh water) or using a Calcium Hardness chemical are the options to lower the level of Calcium Hardness.



    Filter Cleaners do not have a direct effect on water chemistry. They do, however, clean the filter, which does have a direct effect on water chemistry. Filter Cleaners can be liquid or granular. Make sure you purchase the specified Filter Cleaner for your TYPE of filter. Then, read the instructions on the label to determine the amount to add and how it should be added. Note: since Filter Cleaners are less of a chemical and more of a cleaner, it is okay to pour a Filter Cleaner in the SKIMMER. It is NEVER recommended to pour or place any chemical in the skimmer.



    The alkalinity of water is the indication of alkaline salts found.It is not the same as pH but it has a direct effect in pH stabilization.The normal alkalinity level for pool water is 80-120.If alkalinity is outside these limits it will cause unstable pH and before the pH should be stabilised the Total Alkalinity should be adjusted.To lower the Total Alkalinity use Dry Acid.To raise the Total Alkalinity use Sodium Bicarbonate.



    Shocking a pool is mandatory with chlorine, bromine, or any other alternative. As a pool owner, you will become familiar with shocking your pool. Shock is a granular compound. If you use chlorine, you will want to predominantly use a chlorine-based shock such as Calcium Hypochlorite.But, you can supplement your shock schedule with a non-chlorine shock periodically such as Oxamines (Oxygen Shock).



    Ozone is not an "alternative" to chlorine. Rather, ozone is a "supplement" to be used with chlorine. Ozone alone cannot replace chlorine, but when used together, the two are quite effective. Ozone is also quite effective when used with bromine. Although somewhat popular in pools, ozone's niche is with spas (hot tubs).



    Chlorine, by itself, is susceptible to being destroyed by the ultraviolet rays of the sun. Cyanuric Acid, which is typically packaged and sold as either "Stabilizer" will protect chlorine from being destroyed by the sun. Both granular chlorine and chlorine tablets contain Cyanuric Acid as an ingredient but the amount contained is merely a trace. Therefore, the periodic addition of Cyanuric Acid may be necessary to reach 30-50 mg/l.There are tests for measuring the level of Cyanuric Acid. On the other hand excessive Cyanuric Acid above 150 mg/l might cause “Chlorine Lock”.The free chlorine test indicates normal chlorine level but the water looks dull and with a greenish tint.The pool water is “over-stabilised” and algae grows undisturbed.Reducing Cyanuric acid is possible with dilution i.e. adding fresh water.To treat algae you must shock the pool with Calcium Hypochlorite.



    An alternative to chlorine that pool owners use to kill bacteria, living organisms, ammonia, and any other contaminates (such as dirt, debris, or algae spores) that are in pool water. Bromine does come in granular form, but by far, the most common form of bromine is the tablet. The main reason that bromine is not chosen as often as chlorine in pools is that it is fairly expensive. Bromine's niche is with spas (hot tubs), as it is more stable than chlorine in the hotter water temperatures that are associated with spa.




    No Very

    Captcha Image