Calcium 3.5 kg — Bulk Stable Calcium for Reef Aquariums - Aquaforest

Aquaforest Calcium 3.5 kg — stable calcium large format for reef aquariums

The Aquaforest Calcium 3.5 kg ships Aquaforest's high-purity calcium chloride powder in an economy large format. Used in the classic Balling protocol, it prepares a calcium stock solution to dose into the reef tank paired with KH Buffer and Magnesium. Format aimed at established tanks with steady consumption or hobbyists managing several tanks simultaneously.

The 3.5 kg bucket makes about 70 L of stock solution at Aquaforest's official concentration (50 g/L), representing several years of use on a mid-sized reef.

Stock solution and Balling integration

• Official ratio: 50 g of Calcium in 1 L of RO/DI water.
• Boosted concentration: up to 100-150 g/L possible on low-evaporation tanks, within the solubility limit.
• Components Strong: add 5 ml of A Strong + 5 ml of B Strong per liter of solution for the full protocol.
• Balanced dosing: strictly equal shares with the KH Buffer and Magnesium/RMS solutions.

Specifications

• Brand: Aquaforest (Poland)
• Format: 3.5 kg powder bucket
• Type: calcium chloride for large-format Balling
• Compatibility: established reef tanks, multi-tank setups, frag farms

Why choose Aquaforest at ReefSolution

• Calcium 850 g — the trial format to validate the routine before large-bucket commitment.
• KH Buffer 5 kg — the large KH format to pair on high-consumption tanks.
• Magnesium 4 kg — the large Mg format that completes the powder Balling trio.

Frequently asked questions

How long does a 3.5 kg bucket last on a 400 L tank?

On a 400 L tank with moderate SPS/LPS consumption (about 200-300 g of Calcium per month), the 3.5 kg bucket covers 12 to 18 months. On a high-growth SPS tank with sustained draw (500 g/month), duration drops to 7 months.

Can the powder absorb humidity?

Yes — calcium chloride is hygroscopic. Store the bucket tightly closed in a dry location. Humidity exposure clumps the powder without altering composition, but makes weighing less accurate.

How should I store the prepared stock solution?

In an opaque bottle, sheltered from direct light, at room temperature. The solution stays stable for several weeks. Refresh every 2-3 weeks to keep it homogeneous and prevent deposits.