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Magnesium Dosing Calculator
Calculate exactly how much magnesium supplement to add based on your tank volume, current level, and target level.
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Calculate exactly how much magnesium supplement to add based on your tank volume, current level, and target level.
Pre-mixed liquid magnesium supplement from Bulk Reef Supply.
Add this amount of BRS Liquid Magnesium Mix
604.84 mL
20.45 fl oz|120.97 tsp
Spread over 2 days: 302.42 mL/day
Optimal
Ideal range for reef aquariums (~1300 ppm natural seawater) — maintain current dosing.
Large adjustment detected — dose gradually over 2 days (max 100 ppm/day).
Magnesium, calcium, and alkalinity are the “Big 3” reef parameters. Always test all three when adjusting any one of them — they are chemically linked.