Ex-situ bio-methanation carried out by hydrogenotrophic methanogenesis can be used for extraneous CO2 and H2 conversion to CH4. The process has prospective applications in biogas upgrading and for industrial CO2 utilization by conversion into CH4. One of the promising technology for bio-methanation is using biotrickling filter reactors where methanogenic microganism are immobilized over a packing material. In this study a robust method is demonstrated for testing packing materials for the bio-methanation use in a biotrickling filter. This method can help select one of the main variables in the design of the biotrickling filters for the bio-methanation applications.