That's still not true -- the rule is NOT 3-5 ppm for public pools. Where are you getting your information? Are you just making these things up? In the future, please provide references to sources so we don't waste our time correcting this misinformation.My bad - 3 - 5ppm is for public pools. It's 1-3ppm for private. Thanks for catching that.
The EPA requires that swimming pool (and spa) disinfectants pass EPA DIS/TSS-12 and the performance standard for the laboratory test uses a 0.4 ppm FC at pH 7.5 chlorine (with no CYA) reference. All chlorine products that have gone through this do so with 1 ppm FC minimum so that is what is on the labels (except for the NSF Standard 50 "Copper/Silver and Copper Ion Generators" that require 0.4 ppm FC). The EPA has a drinking water limit of 4 ppm FC and that also limits what can be put on chlorine product labels -- again, NOT 5 ppm. However, it is state codes that regulate commercial/private pools and as I describe in this post the maximum FC varies by state up to 10 ppm in Florida (where many pools are outdoors using CYA in hot sun) while the minimum is (again) 1 ppm for swimming pools and in some states it's 2 ppm for spas. You can look at all U.S. state pool codes via this link.
Also, even for Health Canada, this document for British Columbia shows a lower limit of 0.5 ppm with no CYA or 1.0 ppm with CYA for pools (<= 30ºC) while spas (> 30ºC) need 1.5 ppm FC with no CYA or 2.0 ppm FC with CYA. Again, NOT 3.0 ppm minimum. Note that there is NO exception allowed for lowering these minimums further by using copper ions in the water. The same is true for this document for Toronto with 0.5 ppm FC minimum with no CYA and 1.0 ppm FC minimum with CYA with NO exceptions for copper.
Also, even though you are a VP for Sales & Marketing for Argenia Systems, your Google+ page touts the ClearBlue ionizer and on Disqus you also refer to Del Ozone. Again, while it's nice for you to share your personal experiences with a system, you should not ignore the numerous problems people have with ionizer systems causing staining or other issues. One should not project one's own personal experience onto others whose situations may be quite different.
[EDIT] According to this post on another forum, you "represent an ionizer manufacturer". Those in the industry should identify themselves as such. Argenia Systems has not only the railway safety and signaling technology but also the ClearBlue Ionizer™. In this post you refer to ClearBlue being "your wife's company" and you apparently went to work for it in January. That would have been good to know since those with a financial interest in promoting a product have the potential to be biased. I do not work in the pool/spa industry -- I am a residential pool owner. [END-EDIT]