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Fritz Aquatics

Fritz RPM Liquid Magnesium

Fritz RPM Liquid Magnesium

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Regular price $10.49 USD
Regular price Sale price $10.49 USD
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Magnesium plays a critical role in marine aquariums by maintaining a balance between calcium and alkalinity. It is impossible to maintain calcium and alkalinity at the proper levels without also maintaining magnesium. A proper magnesium level is also critical for the health and vitality of many reef aquarium inhabitants. The biologically useful forms of magnesium used in Fritz RPM Liquid Magnesium are utilized in the growth and development of many corals, invertebrates and beneficial calcareous algae. Fritz RPM Liquid Magnesium is formulated using only the highest purity magnesium chloride and magnesium sulfate in a balanced ratio, helping the aquarist to maintain the correct ratio of chloride to sulfate ions found in natural seawater.


Guaranteed Analysis: Magnesium (min) 70,000 ppm


Ingredients: Deionized water, magnesium chloride, magnesium sulfate




Adjustment Dosage: Shake well before using. Begin by measuring magnesium concentration in the aquarium, and determine the amount by which you wish to increase magnesium.

Each mL of Fritz RPM Magnesium will increase the concentration of magnesium in 1 US gallon (3.78 L) of water by 18 ppm. One teaspoon (5 mL) will raise 10 US gallons (38 L) by 9 ppm. To reach the desired magnesium level between 1280 and 1400 ppm, add this product at a daily rate of 10 ml per 10 US gallons daily until the desired concentration is attained, then dose daily or weekly as needed. Do not dose more than 5 mL per 1 gallon per day.


For best results, add RPM Elements to a sump or high flow area of the the tank

No equipment restrictions necessary

No contraindications: can be used with all of our other products and meds

Safe for invertebrates

Easy measuring: the 4 oz, 8 oz and 16 oz bottle caps are approximately 5 mL volume; 32 oz bottle caps are approximately 10 mL volume

Some cloudiness is normal. Allow cloudiness to dissipate completely in before adding Pt 1 and Pt 2

Overdosed? Observe livestock for distress, perform small water changes if needed

Test for magnesium with reliable magnesium test kits


NOTE: If magnesium levels are too low, the addition of calcium and alkalinity supplements will simply result in the chemical precipitation of calcium carbonate. Adjust the magnesium concentration first with Fritz RPM Liquid Magnesium before adjusting calcium and alkalinity.

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