I am originally from Europe.
While there may indeed be no regulations this does not mean Europeans are totally stupid, although I have to admit sometimes we are. The following UK source illustrates what they think the chemical levels should be. While we on the forum may disagree they are not too far different from what is available on most US pool websites. The second line gives an interesting opinion on effects of CYA levels, ph and chlorine on sanitation levels known as the Bartier Disenfection index
http://www.caromal.co.uk/Resource%20Page%204.htm
http://www.caromal.co.uk/Resource%20Page%205.htm
The person that told you this reminds me of insurance agents and financial services persons who tell clients that the IRS has issued a private letter ruling and it is ok to do this convoluted and expensive tax dodge (good commission for them). Private letter rulings are exactly that PRIVATE, that meaning they only apply to the persons applying. They may not apply to the next person applying to the IRS even if the circumstances are nearly exactly the same. So you may end up with some very high tax penalties in the future or in the case of CYA no sanitization
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