Purigen is a synthetic polymer media for removal of organic wastes, that outperforms ion exchange resins on the market by up to 500%. Purigen controls ammonia, nitrites and nitrates by removing organic wastes before they produce these toxic chemicals. Purigen removes a variety of organics without impacting valuable trace elements. Let Purigen polish your water to a cleanliness you will not believe. Amazingly, once Purigen is exhausted, you can actually renew it with household bleach!