Instant Ocean Reef Crystals Aquarium Reef Salt is vitally enriched with extra measures of calcium, selected trace elements and vitamins. The inclusion of these important substances at concentrations greater than that found in natural sea water assures their extended availability in the reef aquarium, thus optimizing the long-term health and growth of corals, anemones, and other invertebrates. Reef Crystals also contains a metal detoxifier that neutralizes excess heavy metals, e.g. copper, often found (in elevated concentrations) in domestic water supplies. And the best thing about Reef Crystals is that it's a one-stop solution - no additional additives required. Features: Formulated to encourage coral growth Includes: 1 Bag of Reef Crystals Reef Salt Intended For: Marine Aquariums Material(s): Salt Color: White Package Weight Expands To: When mixed with water, yields 50 gallons Compatible With: All Marine Aquariums Size: Small.