Some attractive findings were reported by Kousi et al. who developed an upflow fixed-bed SRB to monitor for the treatment of zinc-bearing wastewater. They found that the reactor has a considerable capacity of completely reducing sulfates for initial concentrations up to 6000 mg/L, completely removing soluble zinc for initial concentrations up to 400 mg/L and completely removing TOC for initial concentrations up to 1500 mg/L. The possibility of using SRB for the treatment of an acid mine drainage was also studied.