Reef Code A Balanced Calcium & Alkalinity System Brightwell

In this review of Reef Code A, the focus is on reef keepers who want a precise, science-backed calcium supplement to support coral and calcareous growth. The 5.28 gal formulation supplies the calcium component of a two-part dosing method designed to match natural seawater ionic ratios when used with Reef Code B, and it is most notable for containing not only calcium but supporting major and trace minerals to sustain reef health. For aquarists seeking a robust, American-made product that simplifies calcium and alkalinity maintenance, Reef Code A delivers consistent, measurable results.

Key Features

• Natural seawater ratio: Delivers calcium concentrations formulated to mirror natural seawater when dosed alongside Reef Code B to maintain ionic balance.
• Calcium and multi-mineral supplement: Supplies calcium and essential elements that benefit corals, clams, and calcareous algae for steady skeletal growth.
• Strength advantage: Contains calcium, magnesium, strontium, potassium and trace minerals to provide a more resilient maintenance of aquarium conditions.
• Measured dosing: Clear dosing guidance lets users add 5 ml per 25 gallons every other day to help sustain alkalinity within the recommended range.
• American-made quality: Formulated by a marine scientist and produced in the USA, offering a reliable and scientifically backed option for reef systems.

Who It's For

Reef Code A is best for hobbyists and experienced reef keepers who already dose two-part systems or who are ready to start precise calcium and alkalinity control. It suits aquariums that house corals, clams, and other reef-building organisms that need stable calcium and carbonate availability.

Less suitable for complete beginners who prefer one-bottle solutions or who are uncomfortable testing and adjusting dosing; those users should consider simpler single-part supplements or automated dosing setups paired with routine water testing.

Pros & Cons

Pros

• Supports reef-building growth with a formula that mirrors natural seawater chemistry.
• Includes major and trace minerals for more complete ionic support than plain calcium salts.
• Clear dosing instructions that scale to aquarium volume and treatment frequency.

Cons

• Requires use with Reef Code B and regular testing of calcium/alkalinity, so it is not a standalone fix.

Specifications

Product	Reef Code A
Volume	5.28 GAL
Use	Calcium component of two-part dosing system
Dosing	5 ml per 25 gallons every other day
Treatment coverage	250 ml treats up to 1,250 gallons (when used as directed)
Composition	Calcium, magnesium, strontium, potassium, minor and trace minerals
Origin	Made in the USA

Our Verdict

Reef Code A is a well-formulated calcium supplement for reef aquaria that need accurate, two-part dosing to maintain natural seawater ionic balance. It is good value for hobbyists committed to regular testing and paired use with Reef Code B, because the broader mineral profile supports healthier, more vibrant corals and reduces the guesswork of matching seawater chemistry.

Frequently Asked Questions

Do I need Reef Code B to use this product?
Yes. Reef Code A provides the calcium side of a two-part system and should be used with Reef Code B for balanced carbonate and ionic results.

How often should I dose?
Follow the directions: 5 ml per 25 gallons every other day, and adjust based on test results to maintain alkalinity in the recommended range.

Is this safe for all saltwater fish and corals?
When used as directed and monitored with routine testing, it is formulated for all marine and reef fish tanks and supports reef-building organisms.