768 cubic inches. 0.5-1.5 mm grain size. CaribSea Aragonite Fiji Pink Sand is engineered to be free of impurities such as ash, metals, pesticides, and silica; which allows you to create a safe and beautiful environment for your fish and invertebrates. CaribSea Aragonite dry sands are great for new tanks or adding sand to currently established tanks. Fiji Pink sand is great for all types of tanks and is by far the most recommended type of sand for a reef tank. The particle size is perfect for sand sifting gobies, and other sand-dwelling creatures. NOTE: Despite the name, this sand is NOT very pink.