Hydroton clay pellets are a popular hydroponic medium around the world. Manufactured in Germany the pellets are available in various sizes: 4-8mm and 8-16mm. They are used both for commercial production and for decorative purposes such as a top layer for pot plants.

Because Hydroton is derived from a renewable and plentiful source (clay), it is considered an ecologically sustainable medium. The clay is formed into pellets and then fired in rotary kilns at 1200°C. This causes the clay to expand inside, like popcorn and become porous.

Hydroton pellets are light in weight, do not compact and are completely reusable - they can be cleaned and sterilised after use. They are also inert, pH neutral and contain no nutrients. Because the pellets drain freely and don't hold excessive water, they provide good oxygen levels around the root zone and are particularly suitable for flood and drain systems. They are also used extensively for rose growing.

In drip irrigation, the pellets can be mixed with a medium with better capillary action, so the feed is dissipated broadly through, to prevent salt build-up. Hydroton pellets are quality tested every two months at the University of Hohenheim in Germany. They are exported to 38 countries around the world and are available in 5 litre, 10 litre and 50 litre bags.