CL Free uses electrolysis for oxidation and copper ions for bulk water pool "sanitation", but recognize that copper ions are primarily to inhibit algae growth and that they do not kill nor inhibit fecal bacteria growth at all. As described in technical detail in
this post, copper ions at the concentrations used in pools have absolutely
no effect whatsoever on any fecal bacteria including
Escherichia coli,
Enterococcus faecalis and
Staphylococcus aureus. Copper ions are also slow to kill other bacteria including
Pseudomonas aeruginosa and
Stenotrophomonas maltophilia. It kills
Acinetobacter baumannii about as quickly as chlorine and it kills
Legionella pneumophila somewhat faster than chlorine. Copper ions have little to no effect on many viruses compared to relatively fast kills from chlorine including
Herpes Simplex Virus (HSV),
Vacciniavirus,
Poliovirus,
Coliphage MS-2 and
Influenza.
The CL Free system has not passed
EPA DIS/TSS-12 and cannot claim to be a disinfectant or sanitizer nor can they make bacteria or other pathogen kill claims (the statement "killed by the Ionization process" is likely in violation of EPA FIFRA rules). This system cannot be used in any commercial or public pool in the U.S. or many other countries because it does not use a fast-acting bulk-water disinfectant. There are only three such disinfectants approved by the EPA for pools: chlorine, bromine and Baquacil/biguanide/PHMB. Residential pools are not regulated. Just as you can make yourself sick by leaving a chicken out all day in your kitchen (as opposed to restaurants that have sanitary regulations), you can do most anything you want with your pool.
[EDIT] See also
this Rip-off report and
this A+ BBB rating though given
this ABC News report I would take that with a grain of salt.
This post refers to cloudy water in spite of Cl Free[/url]. [END-EDIT]