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Summer Sale! Use code SUMMER26 for 15% off · Free shipping on orders $49+
Summer Sale! Use code SUMMER26 for 15% off our summer collection! Free shipping on orders $49+

Premium Two-Part Calcium Supplement System

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Original price $91.72
Original price $91.72 - Original price $91.72
Original price $91.72
Current price $40.95
$40.95 - $40.95
Current price $40.95

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SKU B001DD1LGA
Size: 67.6 fl oz (2 L)
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Why you'll love it

This professional-grade two-part calcium system maintains perfect reef water chemistry with the same ionic ratios found in natural seawater, helping your corals, clams, and reef organisms thrive. Keep reading for all the technical details.

Product Description

The Brightwell Aquatics Reef Code A is half of an innovative two-part calcium and alkalinity dosing system that's changing how reef keepers maintain water chemistry. This isn't your typical calcium supplement—it's a scientifically formulated liquid that works with Reef Code B to deliver calcium and carbonates in perfect natural seawater ratios.

What makes this system special is its purity and potency. Unlike many competitors, this formula contains zero phosphates, silicates, or organic pollutants that could harm your tank. The marine scientist who developed this system created something stronger than most competing products while keeping it completely reef-safe.

This 67.6-ounce (2 L) bottle provides long-lasting calcium supplementation for both new tank setups and established reef systems. The liquid format makes dosing simple and precise—no mixing powders or dealing with messy residue.


Interesting Points

Natural Seawater Chemistry

Maintains the exact calcium-to-carbonate ratio found in pristine ocean water, creating optimal conditions for coral growth and calcification.

Ultra-Pure Formula

Zero phosphates, silicates, or organic contaminants means cleaner water and healthier reef inhabitants without unwanted algae blooms.

Professional Strength

More concentrated than typical calcium supplements, so you use less product while achieving better results—perfect for serious reef keepers.

Marine Scientist Developed

Formulated by actual marine scientists, not just marketing teams, ensuring the chemistry works perfectly for real-world reef applications.


Product Specifications

  • Volume: 67.6 fl oz (2 L)
  • Type: Liquid calcium supplement (Part A of two-part system)
  • Phosphate-free formula
  • Silicate-free formula
  • Organic pollutant-free
  • Made in USA
  • Brand: Brightwell Aquatics
  • SKU: ABARCA2L

Usage Notes

  • Must be used with Reef Code B for complete supplementation
  • Suitable for both marine and reef aquariums
  • Test calcium and alkalinity levels before and during use
  • Start with small doses and adjust based on consumption
  • Store in cool, dry place away from direct sunlight

Package Inclusion

  • 1 bottle Brightwell Aquatics Reef Code A (67.6 fl oz)

Ready to achieve that perfect reef water chemistry you've been chasing? This two-part system takes the guesswork out of calcium and alkalinity dosing, giving your corals exactly what they need to flourish in their best colors.


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