Highest quality extruded carbon and resins. Efficient and high speed adsorption rate. From the makers of The Original Chemi-pure for over 50 years. All in one filter media in a bag. Chemi-pure Blue is the ultimate all-in-one marine aquarium filtration media, in an easy to use nylon bag, that offers superior filtration and fantastic results in even the most advanced marine reef aquarium systems. Chemi-pure Blue combines the highest grade of low dust pelletized carbon with premium ion exchange resins to produce a synergistic formula for the health and wellbeing of your aquarium inhabitants. Chemi-pure Blue's proprietary formula significantly reduces organic compounds, odors, phenols, toxins, medications, dissolved metals, phosphates and silicates. Chemi-pure Blue's high-capacity pelletized activated carbon has very low ash content and rinses clear quickly, thus reducing the potential of HLLE within your aquarium. Chemi-pure Blue uses the finest laboratory grade resin technology to rapidly remove organics and phosphates from your aquarium water while raising redox and helping stabilize pH. Chemi-pure Blue's unique formula is the finest marine aquarium filtration media available. Chemi-pure Blue lasts longer and reduces the need for frequent water changes. For a healthy, stable, crystal clear reef or marine aquarium us Chemi-pure Blue! Keep Chemi-pure Blue sealed in container until ready for use. Remove bag from container and rinse gently under clean running water until clear, then place nylon bag in any outside power filter, canister filter, or external sump. For best results water should flow through the filter bag and media. Chemi-pure Blue should be changed every 4 months depending on bio-load. If more than one Chemi-pure Blue filter bag is used change one at a time every week until all bags have been replaced. Use one 5 oz. unit for up to 35 US gallons.