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Brightwell Aquatics Magnesion-P Dry Magnesium Supplement for Reef Aquaria

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Availability: In stock


Quick Overview


  • High-purity powdered magnesium blend
  • Provides magnesium, which helps regulate the balance between calcium and carbonates in aquarium water, and is a component of aragonite, the mineral secreted by reef-building organisms to form skeletal material
  • Stronger and more economical than liquid magnesium solutions; created for hobbyists maintaining multiple reef aquaria
  • Formulated by a marine scientist
  • Weight: 1.2kg/ 2.6lbs
  • Details

    Magnesium helps maintain calcium concentrations by preventing unwanted inorganic precipitation with carbonate ions. No matter how much calcium is added, its natural seawater concentration of 412 ppm will never be sustained until the magnesium concentration begins to approach 1,290 ppm. Keeping magnesium within a range of 1,290-1,320 ppm will maintain the desired balance.

    Instructions and Guidelines:
    Basic: Dissolve 2.5 grams (~1/2 teaspoon) of product per 20 US-gallons of aquarium water in 8-fl. oz. of fresh water; add every other day or as needed to maintain the magnesium concentration within a range of 1,290 - 1,320 ppm. When used in this fashion, 600 g treats up to 4,800 US-gallons (18,170 L).

    Advanced: Create a stock solution by dissolving 20 grams (~4 teaspoons) of Magnesion-P in 8-fl. oz. of fresh water (preferably purified); each ml of the solution will increase magnesium concentration ("Mg2+") in 1 US-gallon (3.785 L) of water by 6.0 ppm. [Reference: Each g of Magnesion-P will increase the Mg2+ in 1 US-gallon (3.785 L) of water by 114.4 ppm.] If initial Mg2+ in the aquarium is below 1,288 ppm, add stock sol’n at maximum rate of 10 ml per 20 US-gallons daily until desired Mg2+ is attained, then dose daily or weekly as needed (see below). Maintain Mg2+ within a range of +/-10 ppm. Once desired Mg2+ has been acquired, measure aquarium's Mg2+ at the same time each day over a one-to-two-week period to determine the daily rate of magnesium uptake (i.e. the decrease in magnesium). To determine daily dosing rate (preferable to weekly dosing): estimate volume of water in entire aquarium system (US-gal.); divide the daily decrease in Mg2+ by 6.0; multiply this number by volume of water in system to obtain daily ml of stock solution required to maintain stable Mg2+.

    Keep out of reach of children. Not for human consumption.

    Magnesium sulfate (anhydrous), Magnesium chloride (anhydrous)

    SKU BT208
    UPC-Code No
    Weight 3.0000
    Dimensions N/A
    Materials N/A
    Brand Brightwell Aquatics
    Color N/A
    Return Policy Standard Return Policy

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