Red Sea Coral Pro Marine Aquarium Reef Salt 22kg Specially formulated for the use with reverse osmosis water Red Sea is please to announce the addition of an innovative new salt formula designed to meet the needs of today`s advanced hobbyist. Coral Pro Salt has been specifically formulated for use with "mineral free" Reverse Osmosis, or soft tap water and contains the elevated levels of calcium and buffer capacity that provide the extended availability of these elements, essential for vibrant coral growth. Utilizing the same natural sea minerals used in Red Sea Salt the new Coral Pro Salt will enable all reverse osmosis users and reef enthusiast a superior product with out the need for immediate supplementation. Chemically balanced formula to support the most delicate Corals and other marine life Reaches a stable, natural pH shortly after mixing Free of Nitrates & Phosphates Produced by a small batch process to ensure homogeneity and consistency of the salt mixture Corals, calcareous algae and other invertebrates use large amounts of Calcium for the building of their skeletons or shells. The Calcium level in natural seawater at 35ppt is approximately 400 ppm. The Coral Pro formula provides elevated levels of calcium at the "lower than natural" salinities preferred in reef aquariums. Table shows concentration at 33ppt - Calcium - 450 Magnesium 1390 22 kg. (48.5 lb.) Bucket/ 640-555 Litres