What Is a Calcium Reactor?

What Is a Calcium Reactor?

A calcium reactor is a piece of equipment used in reef aquariums to maintain stable calcium and alkalinity levels automatically.

It works by:

1. Injecting CO₂ (carbon dioxide) into a sealed chamber
2. Lowering the pH inside the reactor
3. Slowly dissolving calcium-rich media (aragonite)
4. Releasing calcium, alkalinity back into your tank

What other equipment you will need to set up a calcium reactor: 

• Calcium reactor (e.g. Seatorch SM-60X)
• CO₂ cylinder
• CO₂ regulator + solenoid
• Bubble counter
• Feed pump (or manifold from return pump)
• Reactor media (aragonite)
• Optional: pH controller (recommended)

Why Not Just Dose?

Dosing works—but here’s the difference:

Dosing add liquids daily or via doser, but can become unstable as demand increases. 

Calcium Reactor:

Runs 24/7 automatically, adjust once, then minimal maintenance. Scales easily with coral growth. That’s why experienced reefers switch to reactors for long-term stability.

 If you’re serious about coral growth and long-term stability, it’s not just an upgrade—it’s a game changer.

With SeaTorch calcium reactors, you’re investing in precision, reliability, and performance trusted by advanced reef keepers.

SeaTorch calcium reactors are available in 4 different models, with media capacities ranging from 4L to 12L or add-on chamber, allowing you to choose the perfect size for your reef system.

From compact setups to high-demand SPS systems, there is a SeaTorch reactor designed to match your needs.