Ok, so we are focused on using clay and silver to filter water. But what about other materials? Read this November 2006 article (from Penn State Live) to learn more about using scrap tires to filter water.

“Dr. Yuefeng Xie, associate professor of environmental engineering at Penn State Harrisburg, has developed a method that uses crumb rubber to filter wastewater, which can help ease the tire problem and clean up the environment at the same time.

‘My research has found that crumb rubber, derived from waste tires, can be used as a filter media,” Xie explains. “The crumb rubber could be used for treating wastewater, ship ballast water and storm water.'”