Mills CalMag
Updated 18 Oct 2026
Mills CalMag is a highly concentrated liquid calcium and magnesium supplement. It corrects and prevents Ca and Mg deficiencies, supports growth and vitality and stabilises EC, and is essential with soft water or reverse-osmosis water.
Usage & Instructions
Use approx. 1 ml per litre to raise EC. For deficiency prevention use 1 ml per litre (without other additives) at pH 6.5 once per week.
Product Specifications
Description
Mills CalMag supplies calcium and magnesium, the two most common deficiencies in indoor growing. It is used to remineralise reverse-osmosis water and in soft-water areas, to stabilise EC and to prevent deficiencies. Highly concentrated.
Available variants
Additives
All products in the Additives range.
Mills pH-
Mills pH- is a highly concentrated pH down solution (59% phosphoric acid) for lowering the pH of nutrient solutions and irrigation water at every stage of the grow. Recommended pH is 5.5-6.0 for hydro and 6.0-6.5 for soil.
Mills pH+
Mills pH+ is a highly concentrated pH up solution (50% potassium hydroxide) for raising the pH of nutrient solutions and irrigation water at every stage of the grow. Recommended pH is 5.5-6.0 for hydro and 6.0-6.5 for soil.
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