Calmag for water type All - 1L (1.05 qt), case of 12Calcium and magnesium are two of the macro elements that are significant to plants' growth and development. Calcium (Ca) is a critical structural component of cell walls. Magnesium (Mg) is part of the chlorophyll molecule, which makes up the green pigment of leaves and, most importantly, absorbs energy from sunlight, which creates sugars. Our Calmag is highly concentrated and treats prevents calcium magnesium deficiencies. This allows your plants to