Saltwater pools work by using a salt chlorine generator to convert salt (sodium chloride) into chlorine, which sanitizes the pool water. You're essentially getting the same chlorine as you would from adding chlorine directly, but it's generated through this process.
Here's a breakdown of how the process works:
-
Salt is Added: Salt is added to the pool water. The concentration is much lower than ocean water, typically around 3,000-4,000 parts per million (ppm).
-
Electrolysis: The saltwater then passes through a salt chlorine generator (also known as an electrolytic cell). This cell contains titanium plates coated with precious metals.
-
Conversion to Chlorine: An electrical current is applied to the plates, causing a chemical reaction called electrolysis. This process breaks down the salt (NaCl) molecules into chlorine gas (Cl2) and sodium hydroxide (NaOH). The chlorine gas dissolves in the water and forms hypochlorous acid (HOCl) and hypochlorite ions (OCl-), which are the active sanitizing agents – the same as what you get from traditional chlorine.
-
Sanitization: The hypochlorous acid and hypochlorite ions kill bacteria, algae, and other contaminants in the pool water.
-
Reconversion: After sanitizing the water, the chlorine eventually recombines with sodium to reform salt. This salt then cycles back through the generator, continuing the process. However, some salt is lost due to splash-out, backwashing, and other factors, so you'll need to periodically add more salt to the pool.
Essentially, a saltwater pool is a chlorine pool. The difference lies in how the chlorine is introduced. Instead of manually adding chlorine, the pool generates it automatically from salt. This can result in softer water and less chlorine odor, and some people find it easier on their skin and eyes.
