ReMag Magnesium Media for Calcium Reactors is a highly soluble and pure granular product designed to replenish and maintain essential magnesium levels in saltwater reef aquariums. When used in conjunction with a calcium reactor, this specialized media effectively balances the proportions of calcium, alkalinity, and magnesium returned to the aquarium, compensating for the inherently low magnesium content found in most aragonite-based calcium reactor media. It ensures a healthy and successful reef environment by supporting crucial water chemistry parameters. Key features of ReMag include its ability to maintain magnesium without disturbing chloride or sulfate ionic balance, and its highly soluble nature for efficient dissolution. The media boasts a large particle size, typically ranging from 5-10mm, which further enhances its efficiency within a calcium reactor. For optimal results, it is suggested to use ReMag at a ratio of 10% by volume alongside 90% of your primary aragonite calcium reactor media, with a strict recommendation not to exceed 25% ReMag in any setup. This product is best suited for experienced reef aquarium hobbyists who are already utilizing a calcium reactor to manage their tank's water chemistry. It serves as an ideal solution for those aiming to consistently maintain stable magnesium levels within the recommended range of 1200 ppm to 1400 ppm, after initial levels have been established. While ReMag excels at ongoing maintenance, users needing to significantly boost their magnesium levels should first employ a standalone magnesium supplement, and then integrate ReMag to ensure long-term stability.