Expanded Clay Pebbles Grow Media for Orchids, NFT DWC Hydroponics, Aquaponics, Aquaculture LECA Plant Garden Soil Conditioner Amendment Ceramsite Aggregate (4 LB Cz Expanded Clay Pellets)Brand: Cz Garden Supply Features: PREMIUM QUALITY INGREDIENTS: Cz Garden Clay Pebbles are high fired and expanded to create a porous structure that absorbs moisture then releases back to plants when roots need it most. GARDENING Cz Garden Clay Pebbles are all natural and will not leech into your plants, making it ideal for growers of edibles or consumables harvest, such as fruit, vegetables or herbs. Cz Garden Clay Pebbles are guaranteed safe to use