Salifert Profi Test Kits for reef, marine and advanced freshwater aquarists are some of the most precise and accurate test kits on the market. Kits are available for all aspects of the aquarium’s chemistry, covering organic and inorganic pollutants as well as valuable marine trace elements to allow for accurate dosing when additives are required. The kits feature bold colour changes and good colour comparison charts and offer quick and easy water testing. There are 16 kits in the range, and most are suitable for both freshwater and saltwater environments (unless otherwise stated). Magnesium Profi-Test: * Magnesium is present in natural sea water in a fairly high concentration (1350 – 1500 mg/L) and is an essential element of chlorophyll which is necessary for photosynthesis. Without photosynthesis plants, algae and coral would not be able to survive. * Magnesium also helps to maintain the correct combination of calcium concentration and alkalinity as it slows down the formation of calcium carbonate which can absorb many important trace elements within the aquarium. * Maintaining a correct magnesium concentration is therefore very important and is indirectly responsible for fast coral and calcareous algae growth by making it possible to maintain correct calcium and alkalinity figures. * Magnesium is depleted by algae growth and also by the use of excessive kalkwasser or by going far beyond natural calcium, alkalinity and pH values. * The Salifert Magnesium Profi-Test is easy to use and accurate with measurements in steps of 30 mg/L. * Results are not affected by strontium and calcium interference. * Salifert’s Magnesium Additive is ultra pure and does not upset the balance of the aquarium. • Sufficient for 50 tests.