Most are familiar with the idea of chlorine in a given pool, but far fewer have any idea how it actually works or what it’s meant for. At Dolphin Pools & Spas, part of our swimming pool installation and repair services include helping educate our clients on what’s going on in their pool – so let’s do that now.

How exactly does chlorine work in custom pools, and what is it doing for you and your family? Let’s take a look.

Common Pool Chemicals

When you ask what cleans your pool, the actual answer is hypochlorous acid – this is what kills algae and bacteria, and what we measure for when we test for “chlorine.” Some other specific chemicals:

  • Sodium hypochlorite (liquid)
  • Di-chlor (granular)
  • Tri-chlor (stick/tablet)
  • Lithium hypochlorite (granular)
  • Calcium hypochlorite (granular or tablet)

All of these chemicals contain chlorine, hence the prevalence of the term within pool chemicals. After they’ve reacted with water, though, it’s the hypochlorous acid that cleans the pool water, not pure chlorine.

Chemical Process

You begin with pool water and whatever chlorine additive is recommended for your pool. If you have a salt chlorine generator, you use salt. After you pour your additive into water, the reaction creates hypochlorous acid. This is done through two reactions:

Reaction 1

When electricity passes through salt and water, it separates them into gaseous chlorine, sodium hydroxide, and hydrogen. The latter two are ready to go – they don’t need any further reaction. However, the chlorine itself still needs to go through another process.

Reaction 2

From here, the pure chlorine reacts with more water. This turns it into hypochlorous acid and hydrochloric acid – the former is what’s in charge of destroying algae and bacteria, the latter in charge of lowering the pH of your water so it doesn’t become too basic.

For more on how chlorine and pool chemicals work, or to find out about our numerous custom pool options, speak to the pros at Dolphin Pools & Spas today.