The preferred method is to
test the magnesium level in your aquarium, then add Tech•M at the rate of 1 ml per gallon aquarium capacity per day to bring the level to between 1250 and 1350 ppm. This will raise the level by 18.4 ppm per day. As a routine supplement, if not testing, add two teaspoons (2 capfuls or 10 ml) per 50 gallons tank capacity every week in all marine systems.