Sri Lanka imported activated carbon, rezin to make the frist stage of our filter to purify and soften your source water. The second stage is a combination of Tourmaline Stones, Maifan Stones and Bio-ceramic energy balls. During this stage in the process, mineral stones continuously release easily absorbed, ionized minerals into the water, including calcium, iron, magnesium, potassium, zinc and other trace minerals. And has been independently tested to reduce chlorine taste and odour, heavy metals, industrial chemicals and agricultural contaminants.