You can also use the familiar Randy’s mix. All instructions for the above are detailed on the bucket itself. Then simply add Potassium for the complete magnesium dosing additive with essential trace elements. For optimum results the magnesium levels in marine tanks need to be checked regularly to determine the uptake in your system. Simply calculate dosing requirements to suit the depletion rate. After you have determined this, a regular check of the magnesium levels should be made. Your tank will change over time as coral grows, new pieces are added. We have found ideal magnesium levels to be at about natural sea water levels for most aquariums. Levels of 1300-1350ppm are desirable if you want to maintain high levels of growth in a SPS and hard coral dominant system.