Each Pack Contain 30 Lit. ( approExpandedx. 10 kg) Hydroton / Light weight expanded clay agreegate (LECA) Light Weight, Best for Hydroponics and Hobby Growers Useful for Ebb and flow, aquaponics etc.. Hydroston are suitable for hydroponic systems in which all nutrients are carefully controlled in water solution. The clay pellets are inert, pH neutral and do not contain any nutrient value. Hydroston is made from 100% natural resources The radongrow consider expanded clay to be an ecologically sustainable and re-usable growing medium because of its ability to be cleaned and sterilized, HYDROSTON light weight Expanded clay aggregates offers as many superior salient features some listed below : The high quality of our light weight exclusive clay offers healthier and longer plant growth, development and beauty - It allows best aeration for the soil - Maintains the ground level temperature - It allows complete freedom of roots Appearance : : pH value : 7-8 Moisture level : 2% max Bulk Density (BD) : 300 - 400 gm/ltr Size: 8 - 15 mm HYDROSTON has more absorbing capacity than others and retains moisture for much longer saving water resources by reducing watering cycle. HYDROSTON is much more porous and allows maximum aeration for better plant life. HYDROSTON being so light, and prevents water seepage on the flooring so its ideal for roof top and terrace gardening.