The most common type of swimming pool is the chlorine pool, although it is not the only choice available. Saline water pools are becoming an increasingly popular option among homeowners who do not want to deal with the red, itchy eyes, stringy hair and faded swimsuits. Additionally, some people have turned to ultraviolet and ozone filtration systems as alternatives to chlorine. While these systems have some advantages over chlorine pools, chlorine pools come out ahead in certain other regards.

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Chlorine is commonly used to disinfect pools.

Chlorine Is Effective

Chlorine does what it is supposed to do: kill harmful bacteria on contact, to keep pool water sanitized and clear. While chlorine is a powerful chemical, it is completely safe when used in appropriate levels, notes The Good Spa Guide, an independent guide to UK spas, on its website. In fact, some of the adverse side effects commonly associated with swimming in a chlorine pool, such as itchy eyes, are the result of overchlorination.

Chlorine Kills Bacteria Continuously

Ozone filtration systems and ultraviolet filtration systems may kill bacteria in a pool at the time of treatment comparably well to chlorine. Unlike chlorine, however, these systems do not have any residual effects. This means that while they kill bacteria in the water, they will not kill bacteria that enter the water after treatment, notes The Good Spa Guide. Chlorine, on the other hand, acts in two ways: in kills bacteria in the water instantly when added to a pool, and it continues to kill bacteria that may be introduced by new bathers even long after the chlorine was added. In places with warm climates, such as Florida, chlorine is especially advantageous because bacteria and algae that enter a pool after treatment with an alternative system can very quickly turn it into a sludgy nightmare.

All Systems Require Chlorine

Some vendors of saline pools and UV or ozone filtration systems may tell you that these types of pools are a chlorine-alternative. The truth, however, is that both ozone and UV treatments are meant to be complementary to chlorine use, allowing pool owners to lower but not eliminate the amount of chlorine they use in their pools, notes The Good Spa Guide. Additionally, saline pools use chlorine as well, but instead of needing the chlorine to be added manually, most of these pools come with built-in systems that make their own chlorine from the salt content in the pool, notes MacKenzie. Because such alternatives use lower amounts of chlorine, swimmers do not end up with itchy eyes and a chemical smell on their bodies. This can be avoided in a chlorine pool by ensuring you do not overchlorinate.