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Guide to chlorine

What is chlorine?

Chlorine is the most popular type of disinfectant for swimming pools.

The purpose of a pool chlorine is to sanitize, disinfect and oxidize pool water containing contaminants and swimmer waste.

A disinfectant must continually be present in the water so that it can react instantaneously with bacteria, algae and other organic matter that’s introduced to the water. 

Providing measurable sanitizer to your pool water is very important without it all protection for the swimming pool users is lost. 

What is Free Chlorine?

Free Chlorine is the chlorine that is active in the pool and spa water and able to sanitize contaminates.

The level should be between 1 and 3 ppm ( parts per million ) and between 3 and 5 ppm for spas.

What is Combined Chlorine?

Combined Chlorine is chlorine that has already used its ability to sanitize by reacting with contaminates is call combined chlorine.

When the free chlorine has used up its ability to sanitize the water, it becomes combined chlorine. An over-abundance of combined chlorine can cause eye irritation and strong chlorine odors.

Most people think that the strong chlorine smell is caused by too much chlorine in the pool water, however it may actually be that all the free chlorine has combined with swimmer waste and has created those strong chlorine smells.

What is Total Chlorine?

Total Chlorine is the sum of both free chlorine and combined chlorine. 

Periodically you will need to super-chlorinate or commonly known as shock the pool to maintain an optimum active chlorine level to sanitize contaminates in the water. 

Add Tablets

Instead of having to measure anything out you just need to know your pool water quantity and drop the tablets into a floating dispenser, in-line dispenser or skimmers.

Most tablets on the market come available in 70% – 90% active chlorine, one Piscimar Maxiclor 200 tablet will provide 25m3 – 30m3 of chlorine for 1-3 weeks depending on season, usage and chemistry . 

Most pool-owners and pool cleaners will use tablets instead of granules due to either convenience or length of time between chemistry testing.

Adding tablets via skimmers is the most popular method of using disinfectant, they dissolve and return the chemical through the jets back to the pool water, the only problem with this method is that while the pool pump and filter isn’t running the tablets are still dissolving causing high concentration of chlorine in one spot.

Pool plumbing made from flexible pipes will corrode over a short time, its recommended to build pools with PVC rigid pressure pipes.


Floating Dispensers

Floating dispensers are affordable little floating baskets they float on the surface of your pool and slowly dissolve the chlorine tablets into the water.

If your pool is a holiday letting its not recommended to use these as guests tend to remove the float from the water and forget to return it to the water when they’ve finished using the pool which creates problems for the water and costs you money.

Because they rely on the current of the pool water if your pool lacks good circulation this may not be the best option for you.

In-line Feeders

In-line chlorine dispensers or automatic dispensers because you can fill it with as many tablets as it will hold and then set the desired level to automatically dispense the set amounts. 

Just test the levels regularly to make sure its doing its job right!

See: Pool and Spa Test Kits

Related Information

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