Waterbox Magnesium Reef Supplement – 500 ml

Waterbox Magnesium is a liquid supplement for maintaining magnesium in reef aquariums. Keeping magnesium at the correct level helps corals and other reef inhabitants take up calcium and alkalinity, which supports their growth and overall health. Waterbox recommends a range of 1200 to 1400, and each 5 ml dose raises magnesium by 3.75 mg/l in 100 litres (25 gallons) of water.

Key features of the Waterbox Magnesium Reef Supplement

• Maintains magnesium
• Aids calcium uptake
• Supports reef growth
• Target 1200 to 1400 ppm
• 500 ml bottle

Planning your dosing

Magnesium changes slowly, so testing weekly is usually enough to catch small shortfalls. In a 200 L system, 5 ml raises magnesium by about 1.9 mg/l, so moving from 1250 to 1300 would need roughly 135 ml, spread over several days. Bring magnesium into the recommended 1200 to 1400 range before chasing calcium or alkalinity problems, as low magnesium makes those harder to hold steady.

Good to know

Test your water before dosing, add the supplement to a high-flow area and adjust gradually, never raising levels quickly. Keep the bottle closed, out of reach of children and away from direct sunlight.

Waterbox Magnesium Reef Supplement specifications

• Brand: Waterbox
• Brand website: waterboxaquariums.com
• Product: Waterbox Magnesium Reef Supplement – 500 ml
• Recommended level: 1200 to 1400 ppm
• Dose: 5 ml raises magnesium by 3.75 mg/l (ppm) in 100 L (25 gal)
• Category: Fish Water Care