When using a soil medium, the right mix can be a difficult thing to achieve. When doing your own diy hydroponics, the thing to remember about creating a soil medium is a nice mixture of everything. The soil that we stock is designed to be the perfect combination of different parts to ensure your plants love it. It allows a reasonable amount of water to drain away, so that the roots don't rot, and it retains enough water to allow them to absorb all that they can. Soil is a great way to act as a buffer for growing rooms, as when using a pure hydroponic growing system, if you make a mistake it can damage the plant.