As Ben noted, copper and silver ions are not oxidizers so you are basically swimming in your own sweat and urine that builds up over time. Note that the NSF Standard 50 certification for Carribean Clear explicitly states the following:

[1] Copper and silver ion generators are exempt from the Annex H supplemental disinfection
efficacy test which does not address the specific operation of these products. NSF
Listed Ion Generators must be operated with a minimum 0.4 ppm chlorine or 0.8 ppm
bromine. Additional levels of EPA registered disinfecting chemicals may be required by
the regulatory agency having authority.
[2] "Chlorine-Free" logo only applicable when unit used with bromine or bromine compounds
that do not contain chlorine.
You MUST use either chlorine or bromine with such a system in order to be in compliance with the certification. That is because NSF Standard 50 requires that an EPA-registered disinfectant be used that passes DIS/TSS-12.