4 Pounds (1.9 Kilo) Alfagrog Filter media, Porous Lightweight Ceramic Material Alfagrog is a very porous biological filter media that has a large surface area for bacteria to congregate in and clean your pond or aquarium water. Alfagrog is a porous foamed ceramic material, which is lightweight, strong and inert. It's high surface area makes it the natural choice for colonization by micro organisms in biological filtration systems resulting in cleaner water. Selected clays and raw materials are sintered at a high temperature to produce a foamed ceramic porous mass, which is crushed and sieved to a convenient particle size. Alfagrog can also be used as decorative aquatic gravel, aquarium landscaping and in a wide variety of applications. Larger size pieces can be used as a substitute for live rock. Rinse in water prior to use. Benefits of Alfagrog over other filter media: Extremely high surface area Highly porous Inert, pH neutral Lightweight Economical ? 4 Pounds (1.9 Kilo) Alfagrog (E25) Filter media ? Alfagrog Is A Porous Foamed Lightweight Ceramic Material ? Comes In A Toggle Closure Fine Mesh bag 11.5 Inch x 17.5 Inch (30cm x 45cm) ? Easily Cleaned and Long Lasting We sell many aquatic products online for aquariums ponds, Check out our Store! Terms and Conditions. We use all approved methods for accepting payment. Sales Tax will be added to all shipments based regulations. We always try to combine purchases, please contact us directly for a personal service. You will be notified on the day that your goods have been dispatched via e-mail with tracking which is used on all purchases. Please note that if there are any problems, contact us first via e-mail giving full details of any problem along with your user ID. We use USPS and UPS as our chosen carriers shipments to Hawaii, Alaska Puerto Rico may incur surcharges, contact will be made to advise before shipment at which point the order can be cancelled if desired. Orders placed on Saturday/Sunday Public Holidays will be processed next working day. We pride ourselves on excellent feedback, if any part of the buying experience is not to your satisfaction, please contact us to rectify before leaving feedback. By committing to buy you are agreeing to the Terms Conditions stated above.