Hydroponic Growing Media
The clay is formed into round or irregularly shaped pellets and fired in rotary kilns at temperatures up to 1200 degrees Centigrade. The extreme heat causes the clay to expand and become porous, as well as completely sterile. Also known as grow rocks, expanded clay pebbles, and Lightweight Expanded Clay Aggregate (LECA)®, fired clay pebbles are lightweight, do not crush or compact, and are ...