AccuraSea NSW is the original formula developed by nature and proven as a medium for supporting the growth and reproduction of marine fishes and invertebrates for eons. AccuraSea NSW is pure, natural seawater in its most nutrient-poor form as found on coral reefs. We collect AccuraSea NSW near actively growing coral reefs and immediately filter it to 5 microns, then UV sterilize it. This assures that it is free of pathogens and chemically stable for years. Immediately ready for use in all marine aquariums. No added nutrients. Contains all major, minor, and trace elements in the correct proportions as natural seawater because it is natural seawater, period. Packaged in a 4.4 gallon jug in a carton.