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SALIFERT Magnesium Profi Test kit for saltwater (Mg)


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.
The magnesium test kit effectively tests and provides a balanced magnesium aquarium

  • The magnesium test kit can perform up to 50 tests
  • The test will measure accurate steps of colour change in tank
  • Can be used for marine water only.¬†
  • Measurements in steps of 30 mg/L.


1) Using the provided syringe(2ml), add 2ml of aquarium water into the test vial.
2) Add 5 drops of Mg-1
3) Add one spoon of Mg-2 powder to the test vial and swirl for 1 seconds.
4) Place the nozzle firmly on the 1ml syringe and draw 1ml of the Mg-3 reagent
5) Add Mg-3 reagent by the droplets to the test vial until the colour changes to grey or blue. Swirl the test vial in between drops for a second or two.
6) Hold the syringe upwards to take the reading. The magnesium concentration can be obtained from the table.

***Natural Sea water has a magnesium concentration of 1280 ppm.


Keep out of the reach of children! Only for aquarium hobby use.
The use of protective gloves and eye protection is recommended.
Please read the instructions carefully before using the product. 


Salifert is a Netherlands base company that produces top of the line test kits as well as tank additives and foods for marine and reef aquariums.
Salifert is well established and popular with hobbyist for their accurate and affordable test kits.