Calcium Soluble from The Soil Makers is a premium, 100% pulverized limestone calcium carbonate powder designed to lift calcium levels in hydroponic and soil systems—without adding magnesium.

• 38%;
• 95%;
• very low, making it ideal when soils are already high in magnesium;
• 97.0% passing at 100 mesh and 85% passing at 200 mesh, ensuring quick dispersion;
• fine, easy-to-dissolve powder suitable for soil mixes and hydroponic solutions;
• The Soil Makers — backed by hands-on soil science expertise.

Why this matters: calcium is essential for strong cell walls, robust nutrient transport, and steady plant development. With a high Ca content and minimal magnesium, Calcium Soluble provides a concentrated calcium boost without unintentionally altering the soil’s magnesium balance. This makes it a reliable choice when soils already contain adequate or high magnesium levels, where dolomitic lime could tilt the balance unfavorably.

Ideal use cases:

• Hydroponic systems needing a pure calcium source that won’t over-supply magnesium.
• Soil gardens and raised beds where magnesium is abundant and a calcium boost is required for fruiting crops, tomatoes, peppers, and leafy greens.
• Container gardening and potting mixes that call for a finely milled calcium carbonate amendment for steady calcium availability.

What sets Calcium Soluble apart: it delivers reliable calcium with high purity and a predictable dispersion profile, helping you maintain calcium levels where they matter most while avoiding magnesium-driven side effects. Trust The Soil Makers to provide mineral amendments that support healthy root development, strong stems, and better nutrient uptake across your indoor and outdoor growing environments.

This is a pulverized powder (calcium carbonate) - This high quality 100% pulverized limestone is high in calcium and very low in magnesium content. Superior to dolomitic lime when soil is already high in magnesium. Elemental calcium is 38%. Calcium carbonate equivalent is 95%. This product is 97.0 % passing at 100 mesh or 85% passing at 200 mesh.