The ancient Egyptians documented this in 2400 BC. Greek sailors survived months at sea because of it. Five civilizations on five continents, with zero contact between them, independently discovered the same principle. And when NASA needed to purify water 250,000 miles from Earth, they built a 9-ounce device based on the same electrochemistry.

The science is called a galvanic cell. When copper and zinc are placed together in water, they generate a 300-millivolt electrical potential that produces hydroxyl radicals — destroying bacteria, neutralizing chlorine, and trapping heavy metals. The EPA registered copper as antimicrobial. Peer-reviewed studies confirm it kills E. coli in minutes.

Yet the $48 billion water filter industry sells you a plastic cartridge that expires every 60 days.