Thanks for your feedback.I've found your link regarding pool care very educational. At this point, I am still wanting to make a go of the Nature 2 and Potassium shock if I can. It's taken us 5 years to find out why my fiancee always got sick every summer. We finally KNOW he is reacting to chlorine. Even with a perfectly balanced chlorine pool, he cannot tolerate the exposure. It is not worth it to us to risk it again. That said, if there are some helpful suggestions regarding non-chlorine pool maintenence, please post. Thanks again.