- Concentrated powdered magnesium supplement for all marine fish & reef aquaria.
- Magnesium helps regulate the balance between calcium and carbonates.
- Provides aragonite, helping form skeletal material in corals.
- Made in the USA.
Magnesion & Magnesion-P Instructions
- Highly-concentrated ionic magnesium solution.
- 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 such as corals, clams, and their allies to form skeletal material.
- Stronger than most competing products.
- Contains no unwanted organic material such as EDTA, gluconate, or polygluconate.
- Formulated by a marine scientist.
Magnesium plays a vital role in reef aquaria: it helps maintain calcium and carbonate (composing the majority of measurable alkalinity) concentrations by limiting unwanted inorganic precipitation with each other. In the absence of adequate magnesium ions, calcium and carbonate ions bond rapidly, depleting their concentrations in the system and creating the false impression that heavier supplementation is required to re-establish the desired concentrations. 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. Once the balance between calcium and magnesium has been established, subsequent calcium supplementation yields immediate positive results. Keeping magnesium within a range of 1,290-1,320 ppm will maintain the desired balance, and provides enough of the element to reef-building organisms for the formation of aragonite (~0.10% Mg by weight).
The rate at which magnesium is extracted from the water is determined by the stocking density of reef-building livestock, type of lighting, and other conditions; therefore, each aquarium will have different requirements for the rate of magnesium supplementation. Once the rate of magnesium uptake in the aquarium has been determined, the proper dosing rate of this product can be easily calculated. It is recommended that a quality salt mix with the proper (not augmented) alkalinity and concentrations of major, minor, and trace elements be used to establish natural seawater parameters in the reef aquarium, providing a stable ionic foundation on which to build.
All Brightwell Aquatics liquid water care supplements are made with purified water and high purity materials. We develop formulae for aquaria based on empirical data, using observation and measurement rather than theory.
Instructions and Guidelines for Liquid Magnesion
Basic: Shake product well before using. Add 5 ml (1 capful) of product per 20 US-gallons of aquarium water 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, 250 ml treats up to 1,000 US-gallons (3,785 L).
Advanced: Determine the magnesium concentration in the aquarium using an accurate test kit before supplementing. Shake this product well before using. Each ml of Magnesion will increase the concentration of magnesium (“[Mg2+]”) in 1 US-gallon (3.785 L) of water by 26 ppm. If the initial [Mg2+] in the aquarium is below 1,288 ppm, add this product at the maximum rate of 10 ml per 20 US-gallons daily until the desired concentration is attained, then dose daily or weekly as needed (see below). Always try to maintain the [Mg2+] within a range of +/-10 ppm. To determine the dosing rate of this product once the desired [Mg2+] has been acquired, measure the daily rate of magnesium uptake (i.e. the decrease in magnesium) in your aquarium by measuring the aquarium's [Mg2+] at the same time each day over a one- to two-week period. To determine the daily dosing rate (preferable to weekly dosing) for magnesium maintenance: estimate the volume of water in the entire aquarium system; divide the daily decrease in [Mg2+] by 26; multiply this number by the volume of water in the system to get the daily dosage required (ml) to maintain a stable [Mg2+]. Daily dosing maintains a more stable [Mg2+] (and more natural environment) than dosing weekly, in which the [Mg2+] spikes just after dosing and then gradually decreases throughout the course of the week.
Magnesium (min) 2,959 mg/oz. (100,000 ppm)
Purified water, Magnesium sulfate, Magnesium chloride
Instructions and Guidelines For Magnesion-P
Basic: Dissolve 2.5 grams (~3/4 teaspoon) of product per 20 US-gallons of aquarium water in 16-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, 1,200 g treats up to 9,600 US-gallons (36,340 L).
Advanced: First raise the magnesium level using the basic instructions above. Once desired level has been acquired, measure aquarium's magnesium concentration 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 daily). Determine the amount of Magnesion-P to add using this formula: Daily Amt (grams) = Daily Loss (in ppm) x Tank Volume (gallons) / 64. Alternately to measure in liters, use this formula: Determine the amount of Magnesion-P to add using this formula: Daily Amt (grams) = Daily Loss (in ppm) x Tank Volume (liters) / 243.
For example: If you determine that you need to raise the magnesium level in your 50 gallon aquarium by 10 mg/L or 10 ppm, you would add 10 x 50 / 64 or 7.8 grams or about 2.5 teaspoons of powder in as much water as it takes to fully dissolve (about 16 oz. per 2.5 grams or about 48 oz.) of water and mix until clear and cool. Then add that amount to your aquarium.
Caution: Keep out of reach of children. Not for human consumption. Wear rubber gloves and goggles when handling. Contents may get very hot when water is added!
Magnesium sulfate (anhydrous), Magnesium chloride (anhydrous)
Magnesium (min) 24% (240,000 ppm)
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