Kelzyme's element XX, a calcium rich mineral composite, aids in root, shoot, and plant growth. It is granulated for soil application, and can be used with all media. Calcium is critical to the plants of our hydroponic customers, essential for plant cell wall structure and strong stems and leaves. Certain growing media such as coco coir suggest additional calcium, particularly in the first few weeks of a plant's life, due to its cation exchange properties.