Hydroton clay pebbles are pre-washed so less dust. They are a uniform shape.
Expanded clay pebbles are used in hydroponics as a medium to support the plant. They are chemically inert, do not affect pH and provide excellent drainage. They are made from a special type of clay which is heated to a high temperature causing it to pop like popcorn. Because the pebbles 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. Specifically for hydroponic cultivation.