VRI-Hydroton is Mainly used for Hydroponics/Aquaponics ,indoor containers and flower boxes, Bonsai Cultivation, Aquarium, Roof garden, Green vegetables cultivation ,Irrigation,water filtering Extremely stable in both pH and EC,Light weight,strong and thermally insulating.Hydroton has a spherical shape resulting from the pelletizing technique used Particle size : 4-15mm, Water Absorption 18 to 20 % of size. .