Use saltwater prepared with Tropic Marin Pro-Reef Salt for regular water changes in your saltwater aquarium. To start a new aquarium and to re-equilibrate the pH of a tank, add the required amount of Tropic Marin Pro-Reef Salt to water in a clean container while circulating and aerating. The resulting saltwater is ready for use as soon as the salt is completely dissolved. At a temperature of 73-77 degrees F., the specific gravity of the salt water should range from 1.022 to 1.025. A weekly, partial water change, replacing 10% of the total water volume with saltwater prepared with Tropic Marin Pro-Reef Salt, will help to maintain the water quality that your livestock needs for good health.