Chlorine tablets typically are used to inhibit microorganisms in swimming pools. But chlorine stings swimmers’ eyes, dries out hair and skin and has been linked to health problems, including asthma and possibly cancer. What to do…
The water in a saltwater pool is so low in chemicals that most swimmers don’t even bother with goggles. But it’s not like swimming in the ocean—saltwater pool water has only around 10% as much salt as seawater.
Saltwater pools currently make up just 15% of the American residential pool market, but they’re a proven technology that has been around 30 years. They dominate the pool market in Australia. Any pool can be turned into a saltwater pool.
Technically, saltwater pools use chlorine to sanitize pool water, too—they just do so in a very different way. Water is pumped through a “chlorine generator cell” where an electrical current reacts with the salt (sodium chloride) in the water to produce pure chlorine gas. That chlorine kills germs just as chlorine tablets do—but unlike chlorine tablets, it quickly recombines with the sodium, leaving the water largely free of germs and chlorine when it returns to the pool.
The drawbacks of saltwater pools…
Up-front costs are higher. A quality saltwater system typically costs $1,200 to $1,800 installed. (Or $1,300 to $2,000 when retrofitting an existing pool.) That’s much more than the $100 or so for a chlorine feeder. However, the price tag is offset by lower ongoing costs—chlorine tablets cost $30 to $40 or more per month, versus just a few dollars per month in electricity to run a saltwater pool’s chlorine generator plus the cost of salt (three to four 40-pound bags a year at $7 a bag). The breakeven point is about three and a quarter years.
Chlorine generator cells eventually fail. If you buy a quality saltwater system, the cell should last eight to 12 years and cost $400 to $500 or so to replace—but low-end systems often fail in just three to five years.
Saltwater can cause soft stone, such as sandstone, around the top perimeter of a pool to deteriorate. Concrete or tile is a safer choice with a saltwater pool.
Quality makers of saltwater systems include industry leaders Hayward (www.Hayward-Pool.com)…Jandy (www.ZodiacPoolSystems.com/products/jandy)…and Pentair (www.PentairPool.com). There are some fine smaller manufacturers out there, too, including Autopilot (www.AutoPilot.com). Warranties vary from one to three years or longer.
If you don’t want a saltwater system, other types of water-purification systems can be added to your conventional chlorine pool to reduce chlorine use by 50% or more…
Ultraviolet (UV) light pool sanitizers use UV rays to kill microorganisms as they pass through the filter system. Price: Typically $400 to $600 installed.
Corona discharge ozone generators essentially create small lightning bolts in the filter system. This electricity creates ozone that kills microorganisms. Price: Typically $600 to $1,000 installed.
Helpful: Opt for corona discharge if your pool is larger than 18,000 gallons—UV systems often struggle to keep up with high volumes.
Source: Dan Johnson, owner of Swim, Inc., a swimming pool construction company, and Lead Dog Aquatic Consulting, a swimming pool consulting company, both in Sarasota, Florida. He was inducted into the Florida Swimming Pool Association Hall of Fame in 2009 and is a past president of the Florida Swimming Pool Association.