Aquaforest marine test kits are designed to quickly and accurately measure the concentration of magnesium in reef tanks and other marine environments. As corals grow, they intake calcium and carbonate ions and through a biological process forming their hard skeletons and magnesium is required to keep a super-saturated level of calcium and carbonates in solution. If you find you are having trouble keeping your alkalinity or calcium levels where you want them, you may be low on magnesium and magnesium to recommended levels will help keep those in solution. Regular testing of magnesium is significant for any saltwater tank, especially in coral reef tanks along with alkalinity and calcium levels. Specifications: Testing Range - Unlimited Type of Test - Titration Total Number of Tests - 55-60 (depending on reagent volume required per test) What's Included? 1x 3mL Syringe 1x 1mL Syringe 1x Syringe Tip 1x Test Vial 2x Reagent A-Mg 1x Reagent B-Mg 1x Reagent C-Mg 1x Reagent D-Mg 1x Magnesium Reference Solution 1x Instruction Card 1x Quality Certificate