CaribSea Dry Aragonite Special Grade Reef Sand 15 lb</br></br><div style="text-align:left"><b>[Product Information]</b><br><ul><li>A grade of aragonite specifically for plenum type nitrate reducing beds</li><li>Use where a deeper bed is needed</li><li>Allows maximum pH support and dissolution of calcium Carbonate</li><li>Grain size is 10-20 mm</li><li>Made in the USA</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/51oXXbWXFhL.jpg' noproxy></br>