In some instances, marine and reef aquarists may find it beneficial to maintain the magnesium concentration in their aquaria within a range of 1,500 - 1,800 ppm for prolonged periods of time. The period of time will vary between systems and is completely dependant upon the magnesium concentration that is maintained, as well as the extent to which maintaining the magnesium at an elevated concentration is associated with obtaining the desired results.
Additionally, evidence suggests that the specific magnesium salts utilized are important to obtaining the desired results. Hydrat-Mg is a concentrated magnesium solution that makes use of these specific, hydrated (not anhydrous) magnesium salts, in proper ionic ratios. Brightwell Aquatics Magnesion and Magnesion-P are composed of anhydrous magnesium salts, which offer greater purity than hydrated salts; Magnesion is also more concentrated than Hydrat-Mg. Regardless, the conditions that would dictate that the magnesium concentration in a reef system be maintained within a range of 1,500 - 1,800 ppm are, in most cases, more rapidly addressed with Hydrat-Mg than with magnesium supplements composed of anhydrous salts. Choosing to maintain an elevated [Mg2+] for an extended period of time assumes that the aquarist understands the impacts and potential risks that doing so can have on a marine aquarium.
Read all Instructions carefully. Shake container well before using. If using to maintain magnesium concentration within a range encompassing standard seawater concentration, 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 container well before each use. Each ml of Hydrat-Mg will increase the concentration of magnesium ("[Mg2+]") in 1 US-gallon (3.785 L) of water by ~19.5 ppm. If the initial [Mg2+] in the aquarium is below 1,288 ppm, add this product at the maximum rate of 1 ml per 3 US-gallons daily until the desired concentration is attained, then dose daily 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 for magnesium maintenance: estimate the volume of water in the entire aquarium system; divide the daily decrease in [Mg2+] by 19.5; 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+] than dosing weekly, in which the [Mg2+] spikes just after dosing and then gradually decreases throughout the course of the week. Maintaining a stable, elevated [Mg2+] (e.g. 1,800 ppm) for up to 6 weeks may have positive results in some reef aquaria, however corals and other inhabitants may not respond positively in all cases. Monitor system carefully and be prepared to move these organisms to an alternate system with normal [Mg2+] values if necessary.
Brightwell Aquatics Aquarium Supplies
The goal of Brightwell Aquatics is to provide the absolute highest quality, scientifically-sound products and customer service of any aquarium water care manufacturer, and to do it all in a straight-forward and honorable fashion. All Brightwell products are formulated by marine scientists with a passion for the aquarium hobby. They utilize the highest purity ingredients in concentrations that provide the most use to hobbyists. Nearly all Brightwell Aquatics products are over 99.9% pure. The usage guidelines of Brightwell Aquatics products are written in plain language but the company is always available to answer consumer questions. All products are lot numbered for quality control and customer service.
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