CaribSea Arag-Alive Bahama Oolite 20 Lb. Aragonite Reef Sand with Live Stabilized Marine Bacteria : Use alone, or to kick-start our dry aragonite! Arag-Alive has more surface area for bacterial porosity; approximately 20,000 square inches per cubic inch! Arag-Alive will dramatically reduce cycling time in new set-ups because it contains millions of heterotrophic, autotrophic, and chemolithotrophic bacteria. Lowest in phosphate and has no silica. Arag-Alive also provides molybdenum, barium, boron, selenium, beryllium, and other essential ocean trace elements. CaribSea Arag-Alive is not beach collected. This aragonite is not beach zone collected sands: contains no tar, harmful organics, or impurities.