Seachem Laboratories ASM7582 Salinity for Reefs Aquarium Systems, 450-Liter Salinity is specifically formulated for the reef environment Provides ideal seawater concentrations of magnesium, calcium and strontium with proper alkalinity and pH for closed reef aquarium systems A blend of salts specifically formulated for the reef aquarium Contains all essential major minor and trace components found in natural reef waters; no toxic or non-essential components Available in a 450-liter pack