The present invention relates to biofilter systems and the biofilter media employed in such systems, as well as, methods of using same to remove odour causing compounds from waste gas streams. The biofilter media has a plurality of expanded glass granules. Each expanded glass granule has a coating thereon. The coating includes a bonding agent, an adsorptive agent, microorganisms and nutrients. When used in a biofilter system, the biofilter media is highly efficient at removing from waste gas streams hydrogen sulfide at high concentrations in low empty bed residence times.