Instant ocean is the most carefully formulated, most universally preferred sea salt in the world - the perfect solution for creating the ideal marine environment. The # 1 choice of hobbyists, public aquariums, and scientific research facilities everywhere, Instant ocean has set the industry standard for quality, consistency and value for more than 40 years. We will continue to do so for the next 40 years...and on into the future. Superior Formula Free of nitrate and phosphate Contains every major, minor, and trace element necessary for health of even the most delicate marine fish and invertebrates Superior Quality provides a clear ready to use solution in minutes Quickly achieves and maintains the ideal pH No separation during packaging and shipping Superior Convenience No special additives required. Consistent formulation ideal for mixing small or large quantities Twists open, seals easily and completely NEW Twist open lid with rubber gasket. To Open: Firmly tap target with hammer in this direction to the left then unscrew. To Close: Screw lid on tightly, then firmly tap target in this direction to the right with hammer.