de*nitrateª removes nitrates, nitrites, ammonia, and organics from both fresh and marine water. The high porosity of de*nitrateª supports the proliferation of both aerobic and anaerobic bacteria that further remove these toxic aquarium byproducts. Even when exhausted as an organic adsorbent, de*nitrateª continues to be an excellent support for the biological filter and does not have to be removed. This product is sold by volume. Cited weight is minimal weight.DIRECTIONS: For best results, de*nitrateª should be placed to assure the flow of water through it, such as in a canister filter, chemical filtration module, or box filter. Flow rate should not exceed 200 L (50 gallons*) per hour. If higher flow rates are unavoidable, use Matrixª or Pond Matrixª. It is best to rinse off dust before use. Once de*nitrateª has been in use for several days, nitrate concentrations should start to fall and level off gradually at a concentration of about 4Ð5 mg/L as nitrate. As long as nitrate concentrations remain under control, the product is not exhausted. Each 1 L of de*nitrateª treats about 200Ð400 L (50Ð100 gallons*), depending on initial nitrate concentration and the current biological load. Enough should be used to remove nitrate at a rate at least as fast as the rate of formation. If - UPC: 116013802