The performance of aerobic bioreactors loaded with novel biomass support (the KMTi?½ support particles) during the treatment of tanning industry wastewater is presented in this paper. The wastewater samples were collected from TANWAT Company in Njombe, which extracts tannins from barks of the wattle tree. The wastewater generated from TANWAT is very acidic with high loading of organic compounds, which are very complex and difficult to biodegrade using conventional methods. The paper introduces a new technology for treatment of heavily loaded industrial wastewater, like tannins, that is the Three-Phase Fluidized Bed Bioreactor (TPFBB) which utilizes the KMTi?½ support particles. Bench scale bioreactors (BSBs) were used to establish the suitable inoculum for use in the TPFBB. To establish the effect of the KMTi?½ support particles, the BSBs were operated with and without the biomass support particles (BSPs). The BSBs were also inoculated with different types of inoculum (waste stabilization ponds (WSP) and rumen fluid (RF) inoculums) to establish the suitable source of microorganisms. Control samples were also implemented accordingly. The results show that the WSP was a suitable inoculum for which high chemical oxygen demand (COD) removal efficiency and tannins concentration reduction efficiency (TCRE) were observed. Tests conducted in the TPFBB with initial COD of about 13,200 ppm shows that the reactor is capable of biodegrading the tannins (at 85% efficiency) after aeration times of up to 7 days in recirculation mode. The final COD values of 1,000 ppm were reached in most cases. For final discharge, however, such a final COD necessitates the use of sub-surface flow constructed wetland (SSFCW) coupled to the TPFBB for final smoothing of the effluent. The TPFBB is recommended for treatment of tannin wastewater to minimize chemical pollution in the receiving water bodies.