"Chlorine has long been the industry standard to keep pool water clean and clear, but consumer demand for alternatives has prompted the emergence of new technologies, including the saltwater systems that came into vogue a few years ago and the copper-and-silver ionization and ozone-gas systems that are increasingly popular."
""I don't like the stuff that goes into swimming pools," said Philip Daughtry, a Topanga Canyon poet who often swims in the koi pond he refers to as his "backcountry swimming hole." Daughtry's swimming pond was constructed by Environmental Sculpturing in Topanga Canyon, the outfit that also helped to design and install the Santa Monica pond being built in a Zen-influenced, Minimalist style.
Natural swimming ponds take many shapes. Some look like traditional pools with poured concrete foundations, hard edges and straight lines. Others take forms that more closely mimic nature, with gently sloping and planted edges."