Royal Nature Magnesium Professional Test

Keeping the tests user friendly was a big concern for us and our chemists were able to get the magnesium test to two steps only. Having clear color changes in the titration was also key, to help eliminate user confusion on guessing if they are reading the test accurately.

Each test uses a two-part chemical reaction and a syringe to add water until the final color is hit. We also guarantee you’ll get 50 tests out of each magnesium test.

In theory we are using the same ideas as in Ca test. The chemical solution here is very sensitive to PH and therefore we need to use a strong buffer.

Not as in the Ca test, our challenge here is to precipitate the Ca first and then find Mg levels. Our way of testing Mg is a bit different and based on direct titration where we add sea water to the chemical solution.

A special correlation table where we can correct Mg levels by knowing Ca levels without the need to precipitate it. Our ability to produce in small batches is critical to achieve analytical calibration which is a key to our tests accuracy.

MAGNESIUM TEST INSTRUCTIONS - 2 steps only

Each kit will give you 50 tests.

We recommend doing the Calcium test first.

1. Using the 3 ml syringe add 2 ml of Mg-1 to the test vial.

2. Add one flat 0.15 ml scoop of Mg-2 powder to the test vial and swirl.

• The solution should appear this color: 

3. Using the 1 ml syringe, place the plastic tip firmly and draw up the aquarium water until the lower end of syringe's black rubber is right on the 1.00 ml mark. Before this step, ensure that the plastic tip is empty of liquids and that it's submersed in water the entire time to avoid air entering to the syringe.

• The presence of a layer of air between the liquid and the black part of syringe is normal and will not affect the result. (The normal air layer you should see is equal to 0.1 ml.)

4. Begin adding aquarium water to the test vial one drop at a time, swirling a little after each drop until the solution appears this color: 

Attention: before any use of the vial test, make sure it is washed with RO water only and dry it up with a soft paper.

• If the solution in the test vial does not reach this color and you have used all the aquarium water in the syringe, return back to step 3 (It means that concentration of magnesium is below 970ppm).

• If after adding another 1.00 ml of water a second time, the color is not changed this means the concentration of magnesium is below 360ppm.

Faster test can be achieve without the plastic tip with a potential mistake of 2%.

5. Note the position of the lower black part of syringe (each division corresponds to 0.01 ml) and obtain the magnesium concentration from Table 1. Readings should be taken at the position of the lower end of syringe's black rubber.

• If you needed to return to step 3 a second time then use Table 2 to obtain the magnesium concentration. The normal concentrations for magnesium are between 1280-1540 ppm (salinity related).

The result is accurate when the concentration of calcium is between 350-450ppm. If the concentration of calcium is not in this range then you can correct the result from this table:


NSW Magnesium is around 1350. Our recommendation is to keep Magnesium levels in the tank between: 1290-1450 PPM. In case of low Magnesium use Royal Magnesium Chloride to keep parameters between: 1290-1450 PPM.





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