Caribsea special grade reef sand 1.0–2.0 mm diameter grain size. A revolution in reef-keeping! This is the one you’ve been reading about in all the hobbyist publications. This grade of aragonite is specifically engineered for plenum-type nitrate reducing beds or anywhere a deeper bed is called for. The pore water space created by precision grading also allows maximum pH support and dissolution of calcium carbonate.
CaribSea Aragonite buffers to the highest pH and delivers more calcium, carbonate, and trace elements than any other substrate. Little or no rinsing required, aragonite keeps aquariums healthier, longer.