Reef Charge  |  SKU: RC-CAL-16

Calcium20+

Regular price $16.99
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Calcium²⁰+ is a concentrated calcium supplement formulated for reef aquariums. It is intended for maintaining and correcting calcium levels that fall below the natural seawater range (400–450 ppm). Unlike blended maintenance formulas, Calcium²⁰+ provides calcium alone, making it ideal for safely raising levels without disturbing balance. Each mL increases calcium by approximately 25 ppm per 1 US gallon (3.8 L).

Instructions

Test calcium with a reliable reef test kit before dosing.

Calculate dose: 1 mL per 1 US gallon = +25 ppm calcium 1 mL per 10 US gallons = +2.5 ppm calcium

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

Example: In a 100-gallon system, 200 mL raises calcium by approximately +50 ppm.

Ingredients

  • Purified RO/DI water
  • USP-grade calcium 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 15 °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.

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ALK Alkalinity
Reference range 7–13 dKH
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Carbonate buffering and daily calcification demand.

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