Brightwell Aquatics Magnesion 250mL. 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).
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