Many growers use a soil-like mix consisting of perlite mixed with other things such as coco coir or vermiculite. Both perlite and vermiculite are synthetic materials that are air puffed or heated until puffed (respectively) to produce a light and porous material that is excellent for oxygen retention. This media has many of the same benefits of coco, but any hydro system using it needs a very good filtration system to keep particles out of their recycled solution and water pumps.

Growstones

Growstones are recycled glass that’s been mixed with calcium carbonate to form a lightweight and porous substance similar to lava rocks, as in the case of pumice. Growstones are entirely sustainable and have fantastic water and air retention. As a trade-off, growstones are almost impossible to clean and re-use. Their porous nature leads to roots growing within the rocks and leaving behind plant matter that can affect your next crop. Be careful when transplanting from a growstone medium as they grip roots more easily, which can lead to root damage.

Depending on whether you need water retention or drainage, are worried over oxygen content of your water, or just need to avoid pH imbalanced mediums, there is always an option available. What do you use for your media and system? We’d love to hear about it in the comments below. You can also send us images of your systems through Facebook, Twitter, Google Plus, LinkedIn, Pinterest, or Instagram!