Our hydroponic media comes in the shape of clay pebbles, vermiculite and perlite (as well as Rockwool - see the Rockwool category for this option). Clay pebbles rank among the most popular growing mediums we sell because they are clean, pH neutral, pH stable and well suited to most systems - including flood & drain, drippers, hand-watered pots and Wilmas! Perlite is a very airy growing medium that aids drainage and perfectly compliments the water retentive qualities of Vermiculite when both used together. For further advice on hydroponic media, visit one of our stores or call 0845 345 5178 and speak to an expert advisor at GroWell.