Reducing chemical use has great appeal, but it is critical to keep the family swimming pool free from dangerous germs. There are chlorinated, reduced-chlorine, and chlorine-free sanitization systems. The treatment system a homeowner chooses will depend on personal views, the amount of use the pool receives, costs, and convenience.
Why Treat the Water
Treating the swimming pool is important for two reasons: To protect the pool and protect the people. Balanced pool water is not too acidic or too alkaline, which protects the pool against corrosion. Having the right level of calcium ion concentration prevents surface etching and calcium scale from forming.
People can get very sick from dirty pool water. It's important to protect the health of the swimmers by controlling disease-causing germs and eliminating nuisances like algae. While some bacteria can cause vomiting, cramps, or severe diarrhea, the most common bacterial infections are ear aches and minor skin rashes that resemble flea or chigger bites. Periodic ear aches and minor red rashes that come and go should be a red flag to pool owners that their pool is being under-treated. While algae is an eyesore, it is not a health threat.
Treating Pools for Germs
Whatever system you choose, it's vital to have a clean pool. Waterborne germs are common, according to Roy D. Vore, Ph.D, of DuPont Chemical Solutions Enterprise and a member of the Association of Pool and Spa Professionals (APSP). Many germs can cause serious or life-threatening illnesses like diarrhea, skin infections, outer ear and eye infections, respiratory and brain infections, and hepatitis A.
Chlorine, in its various chemical forms, has been sanitizing pools in the United States for years because it's inexpensive and it works. Chlorine has its downside, too. Whenever chlorine is added to pool water and organic compounds are present, disinfection by-products will be formed. According to Dr. Vore, up to 90% of chlorine added to a pool is consumed in oxidizing organic waste. Another way to look at this is that as little as 10% of chlorine added to a pool is used to control germs and algae. Chlorine also fades swimsuits and can cause skin irritation, eye irritation, and breathing problems. There are several products on the market that offer alternatives to traditional chlorine treatment.
Bromine. Bromine is a member of the halogen family, which includes chlorine. As such, it can cause some of the same breathing and skin issues as chlorine. But, unlike chlorine, when bromine comes into contact with nitrogen and ammonia from sweat, waste, or urine, it forms compounds but continues to sanitize the pool. It is not as stable as chlorine, though. Bromine burns off rapidly in the sun, leaving the pool with little or no sanitizing agent to protect it.
PHMB. Pool owners may not be familiar with polyhexamethylene biguanide or PHMB, known in the U.S. under such brand names as Baquacil® and SoftSwim®. In general, PHMB is more stable than chlorine, less irritating to skin and eyes than chlorine, and won't bleach bathing suits or pool liners. But many pool owners have had trouble with PHMB because of the cost, maintenance requirements, and inability to control water mold and algae.