Quantum Aragonite A - Calcium

Quantum Aragonite A is a concentrated liquid calcium supplement and the first part of Quantum's three part Aragonite reef dosing system. Calcium is one of the building blocks your corals, clams, and coralline algae pull from the water every day to grow new skeleton and shell. Aragonite A replaces it in a clean, reef safe form so your tank never runs short. Pair it with Aragonite B (Alkalinity) and Aragonite C (Magnesium) for complete, stable chemistry, and explore the rest of our reef additives and supplements.

Why Calcium Matters

Stony corals (SPS and LPS), clams, snails, and coralline algae all build their structures from calcium carbonate. A growing reef can pull calcium down quickly, and when it drops, growth slows and tips can pale or recede. Aragonite A lets you hold calcium in the ideal 420 to 440 ppm range. Magnesium (Aragonite C) keeps that calcium and your alkalinity in solution, and alkalinity (Aragonite B) supplies the carbonate side of the equation, which is why the three are dosed as a set.

Features

Choose Your Size

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Detailed Size Specifications

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Which Size Is Right for You?

250 ml — Nano and pico reefs, or a low commitment way to start the Aragonite system.

500 ml — Small reefs with a light to moderate calcium draw.

1 L — The sweet spot for most mid size reefs. Best mix of value and freshness.

5 L — Large SPS systems or multiple tanks where you want the lowest cost per ml.

How to Dose

Always test before you dose. Use a quality calcium test kit, then add Aragonite A to bring calcium into the 420 to 440 ppm range, raising it no more than about 50 ppm per day. Once you hit your target, dose a small daily amount to replace what your corals consume. Follow the dosing guide on the bottle and adjust to your own test results. Keep calcium, alkalinity, and magnesium in balance by dosing Aragonite A, B, and C together, and pick up a reliable kit from our water testing collection.

FAQ

Do I have to use all three Aragonite products?
For a thriving reef, yes. Calcium, alkalinity, and magnesium are consumed together and depend on each other. Dosing only calcium will eventually pull the other two out of range.

What calcium level should I aim for?
Most reef keepers target 420 to 440 ppm. Test, then dose Aragonite A to reach and hold that range.

Can I use this in a fish only saltwater tank?
You can, but the main benefit is for reef tanks with corals, clams, and coralline algae that actively use calcium.

How is this different from Quantum Easy E Calcium?
Aragonite A is the single calcium component of the three part Aragonite system. Easy E Calcium is part of a simpler two part approach. Both raise calcium; choose the system that fits how you like to dose.