I've posted in the past in detail about drinking water, water collection, impurities and additives in municipal water, and how to find a decent water filter. The brand Nux and I decided to purchase from was Berkey, and I wanted to post a link to their web site - Berkey Filters. Take a look and find out why they're the cleanest, greenest option (especially if you're using rainwater catchment). They also offer handy filters that take the fluoride out of your municipal water. Hold the sedatives, Uncle Sam!