Biological Filter Mini Bacteria House Ceramic Rings - 450 grams in Nylon Mesh Media Bag with PLASTIC zipper (not metal) to prevent rust/oxidation! • Ponds • Aquariums by Cz Garden</br></br><div style="text-align:left"><b>[Product Information]</b><br><ul><li>1 Reusable nylon-mesh bag filled with 450 grams of filter rings</li><li>Long lasting， highly porous ceramic material removes ammonia & nitrites</li><li>Nylon Mesh bag includes a PLASTIC zipper (not metal) to prevent rust! Suitable for both freshwater and saltwater filters</li><li>Honeycomb interior surface increases surface area for bacteria colonization 10x's more than ceramic rings!</li><li>Only available from Cz Garden Supply (TM)， USPTO and Amazon Brand Registry Protected</li></ul></div></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br></br><img src='http://ecx.images-amazon.com/images/I/51Z0q0x%2Bk4L.jpg' noproxy></br><img src='http://ecx.images-amazon.com/images/I/51ejpqVAH6L.jpg' noproxy></br><img src='http://ecx.images-amazon.com/images/I/61UEPriHFaL.jpg' noproxy></br><img src='http://ecx.images-amazon.com/images/I/51fVQKWcvqL.jpg' noproxy></br>