Laguna PowerFlo 1000 Biological Filter Media， 6.6-Pound<div style="text-align: left;"><strong>[Product Information]</strong><br><ul><li>Laguna Lava Rock is the ideal host for large populations of beneficial bacteria.</li><li>Suitable for most underwater and external pond filters</li><li>Placed in the appropriate pond filter media chamber</li><li>Filter out harmful toxins and creating optimal conditions for clean and clear pond water</li><li>This product weighs 6.6-pound</li></ul></div><img src="http://ecx.images-amazon.com/images/I/51eJRtT7O3L.jpg" noproxy>