Red Sea Magnesium Test Lab
When to Test for Magnesium
The frequency of testing for magnesium is inversely proportional to the frequency of water changes. Aquariums with sophisticated filtration or advanced biological systems that require less water changes should be tested for magnesium every week and supplemented accordingly.
Aquariums that rely on frequent water changes need only to be tested monthly. If your aquarium suddenly has a low alkalinity, test for magnesium, as this is a potential cause of the alkalinity drop.
Directions for Use:- Clean the test tube by rinsing it with tap water. Clean the large (5 ml) syringe by rinsing it with the water to be tested.
- Using the large (5 ml) syringe provided, place exactly 2 ml of the water to be tested into the test tube. Avoid drawing air bubbles into the syringe.
- Add 5 drops of Magnesium Reagant A, shaking for 15 seconds after each drop.
- Add 5 drops of Magnesium Reagent B and shake for 2 seconds.
- Wait 1 minute; the color of the liquid should be pink as the start color on the color card and a precipitate will form on the bottom of the test tube.
- Place the needle of the small (1 ml) syringe provided and draw exactly 1 ml of Magnesium Reagent C into the syringe. Avoid drawing air bubbles into the syringe, as this will affect the accuracy of the test. (Note: Reagent C is packed with a dropper inserted in the neck of the bottle to prevent leakage during shipping. You must remove this dropper before inserting the syringe in the bottle.)
- Hold the syringe with Reagent C in one hand while holding the test tube in the other.
- Add 0.4 ml of Reagent C to the test tube (i.e. by depressing the plunger to the 0.6 mark) while mixing gently, continue adding Reagent C one drop at a time. After each drop, mix for 2 seconds and compare the color of the liquid in the tube to the blue "end" color on the color card. Stop adding Reagent C when the end color appears in the test tube. Note: After a few minutes the liquid in the test tube will turn from blue to violet. This color change has no significance for the test.
- Note the amount of Reagent C used.
- Return any unused quantity of Reagent C to the bottle and rinse both syringes with tap water.
- Clean the test tube thoroughly immediately after use. If left for a long period, a residue will form inside the tube that will affect the results of future tests. Should this occur, wash the test tube with a slightly acidic solution such as vinegar.
- Use the table and/or formula below to calculate the magnesium concentration.
Magnesium Concentration (ppm) = Amount of Reagent C used (ml) X 2000
