Use of Chlorine in a Swimming Pool



Follow this easy guide to understand why and how to correctly use chlorine in your swimming pool.


Why Is Chlorine Necessary?

Although the duty of a pool filtration system is to keep the water clean, chemicals are still needed to precisely regulate the cleanliness of the water. It is crucial to carefully maintain the chemical balance of pools. Why is this so? One reason is that micro-organisms, such as bacteria, can grow in the water. A pool filled with untreated water would be a perfect place for the spread of disease-carrying pathogens. In addition, an imbalance in the water can damage the pool and its equipment, it can also cause cloudy water or irritate the skin and eyes of swimmers.

Chlorine Granules or Chlorine Tablets; What's the Difference?

Acti Long Tab stabilized chlorine tablets are highly concentrated, disc-shaped, compacted products; they often contain about 90% chlorine. Due to their high concentration, they dissolve over a longer period of time in the pool. Acti Shock chlorine granules (or shock chlorine) are in granule form and are simply dispersed in the pool. Because they are smaller and less concentrated (about 60% active chlorine versus 90% in tablets), they dissolve faster and do not require a dispenser.

How Does Chlorine Work?

When Acti Shock granulated chlorine or chlorine tablets are dissolved in your pool, the chlorine combines with bacteria and other organic matter to neutralize harmful impurities. By killing these harmful contaminants, the chlorine becomes inactive, the chlorine and bacteria that have combined together are then called "combined chlorine". This newly formed combined chlorine must be removed from the pool in order to keep the water clean and healthy, it is eliminated by "shocking" the pool very effectively with Acti HP Shock. Super chlorination or "shock disinfection" means a drastic increase in the pool's chlorine level for a short period of time, to a level high enough for the combined chlorine to be eliminated.

Correct Use of Chlorine:

  • Read and carefully follow the precautions for use specified on the labelling of chlorinated products (risks and safety instructions). Chlorine is a harmful and dangerous product for the environment, its use must be done with precautions (gloves, glasses, if necessary mask).
  • Never mix different types of chlorine in a concentrated state: slow chlorine (trichloroisocyanuric acid) and calcium hypochlorite react violently when in contact and in the presence of moisture.
  • Use the appropriate type of chlorine for the desired treatment (shock chlorine for shock treatment of the pool and stabilized chlorine for prolonged chlorine action).
  • Regularly check the chlorine level in the pool, it should be between 1.5 and 2 mg/l with a pH close to 7.2 (between 7.0 and 7.6).

Improper Use of Chlorine:

  • Do not follow the advice of specialists and recommendations for use.
  • Depositing chlorine pebbles directly in the pool will cause the bottom of the pool to deteriorate, for example: stain on the liner (preferably deposit your pebble in the skimmer).
  • Put a larger quantity of pebbles in the skimmer thinking that the treatment time will be longer. The treatment will remain the same, but the level of chlorine will become too high and may lead to saturation of the product's action.

What is a Chemical Diffuser?

The idea of not having to add chlorine to the pool for a few weeks is very attractive to many people. Chemical feeders, also known as pool chlorinators or pool brominators, are fairly simple devices that contain larger amounts of chlorine or bromine and gradually release these chemicals into the pool. These pool chemical dispensers provide homeowners with a reliable and easy method of administering the right amount of chlorine. Pool chlorinators help ensure that your pool water has the right chemical balance. 

Floating chlorine diffusers are the most popular and affordable pool supply devices on the market. They are practical and adaptable and can be used in any type of pool, whether it is inground, above ground or in a spa. Floating diffusers work by allowing the water to interact and dissolve the chlorine tablet as it floats in the pool water. This allows a constant flow of chlorine into the pool until the chlorine tablet is completely dissolved.

Chlorinators are water purification systems that convert salt into natural chlorine and therefore into disinfectant. They are installed in the technical room of swimming pools. The installation of the control box and the electrolytic cell is done on the delivery pipes of the hydraulic circuit. This type of chlorinator is more common for underground pools and must be installed by a specialist.

Don't hesitate to contact us with any questions!


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