Researchers at Mississippi State University have been studying the effectiveness of the attached growth process for swine wastewater treatment and odor abatement for the past three years. Organic (kenaf, hibiscus cannabis, and pine chips) and inorganic (river-rocks and biorings) attached growth media have been operated with and without added microbial seed. Wastewater samples were analyzed by human olfactory panels and a variety of wastewater quality methods. Olfactory panel results show that all media removes the swine odor content of the wastewater within 48 hours of operation. Water quality analysis shows an approximate 90% removal in COD. The addition of the microbial seed improved the capacity of the attached growth bioreactors to remove total solids, volatile solids, and phosphorous versus the non-seeded bioreactors.