Mother Earth® Growstone Chunky Growing Media is the perfect growing media for use in hydroponic growing systems as simple as manually irrigated containers or as advanced as automatically drip irrigated containers, Ebb-Flow systems and NFT tables. It replaces strip-mined materials like clay pebbles or stonewool, reducing environmental degradation. Mother Earth® Growstone Chunky Growing Media is designed to allow for rapid moisture absorption and enhanced drainage and oxygenation. 100% Recycled. 100% American made.