Plain Milk of Magnesia (MoM) should be used in the recipe. The "active" ingredient should only be magnesium hydroxide [Mg (OH)2], 400 mg per teaspoon (5 ml), and the "inactive" ingredient should only be purified water. 41.7% by weight of magnesium hydroxide is magnesium (Mg), so 5 ml of MoM has 167 mg of Mg, and 1 tablespoon has 500 mg of Mg (1 tablespoon = 15 ml).
To prepare the water follow these steps: 1. Chill completely to refrigerator temperature a 1-liter bottle of fully carbonated water. Carbonated waters such as Canada Dry Seltzer, which consist of only water and carbon dioxide (CO2), are suitable. Club sodas such as Schweppes Club Soda are also suitable; they are carbonated water with a small amount of added sodium. ? 2. Shake well the bottle of MoM, then measure out as accurately as possible 3 tablespoons (45 ml) and have it ready. The plastic measuring cup that comes with the MoM is accurate and ideal for the purpose. 3. Remove the bottle of carbonated water from the refrigerator without agitating it. Open it slowly and carefully to minimize the loss of CO2. As soon as the initial fizzing settles down, slowly add the pre-measured MoM. Promptly replace the cap on the water bottle and shake it vigorously for 30 seconds or so, making the liquid cloudy. After ½ hour or so the liquid will have cleared, and any un-dissolved magnesium hydroxide will have settled to the bottom of the bottle. Again shake the bottle vigorously for 30 seconds or so, making the liquid cloudy again. When the liquid again clears all of the magnesium hydroxide in the MoM should have reacted with all of the CO2 to become dissolved (ionized) magnesium and bicarbonate. However, if a small amount of un-dissolved magnesium hydroxide still remains in the bottom of the bottle as a sediment it may be ignored. This 1 liter of concentrated magnesium bicarbonate water will have approximately 1500 mg of magnesium and approximately 7500 mg of bicarbonate. It should be kept in the refrigerator. You may note that the sides of the bottle "cave in" when the liquid clears. This is a sign that the reaction is complete. 4. To make 4 liters of magnesium bicarbonate drinking water with approximately 125 mg of magnesium and approximately 625 mg of bicarbonate per liter and a pH of approximately 8+ measure and transfer 1/3 liter of the concentrate (333 ml) into a 4-liter container. Fill the container with 3 2/3 liters of plain or purified water, as desired. Magnesium dissolved in water (ionized) is considerably more bioavailable than is magnesium in solid tablets or capsules. About 50% of the magnesium contained in magnesium/bicarbonate water is absorbed[4,5]. This is 12 times better than the absorption rate for magnesium oxide. So drinking 1 liter of magnesium/bicarbonate water per day would correspond to taking five 500 mg magnesium oxide tablets daily. The alkaline magnesium/bicarbonate water should be consumed throughout the day. It can be consumed with a meal, but not in such quantities that it results in dilution of stomach acid. Anyone not in the habit of drinking water should begin by consuming small daily amounts, and should take at least a month to reach a consumption of 1 to 2 liters per day.
