Magnesium¹²+

Magnesium¹²+ is a concentrated magnesium supplement formulated for reef aquariums. It is intended for occasional correction when magnesium levels fall below the natural seawater range (1,280–1,350 ppm). Unlike daily maintenance formulas, Magnesium 12+ delivers magnesium alone, without additional trace ions, making it ideal for safely raising levels without disturbing balance. Each mL increases magnesium by 10 ppm per 1 US gallon (3.8 L).

Instructions 

Test magnesium with a reliable kit before dosing.

Calculate dose: 1 mL per 1 US gallon = +10 ppm magnesium 1 mL per 10 US gallons = +1 ppm magnesium

Dose safely: Do not increase magnesium by more than 50–100 ppm per day. Add dose gradually into a high-flow sump or display area. Re-test magnesium after 12–24 hours before repeating.

Example: In a 100-gallon system, 500 mL (≈1 bottle) raises magnesium by ~+50 ppm.

Ingredients

• Purified RO/DI water
• USP-grade magnesium salts

Storage

• Store tightly sealed in a cool, shaded location (≤25 °C / 77 °F).
• Protect from direct light.
• Shelf life: 24 months.
• Crystals that may form below 10 °C will redissolve when warmed and shaken.

Safety Information

• Not for human consumption.
• Avoid contact with eyes, skin, and clothing.
• If on skin or in eyes, rinse with water for 15 minutes.
• If swallowed, rinse mouth and seek medical advice.
• Wash hands after use.
• Keep out of reach of children and pets.
• Discard according to local regulations.

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