The success of gravity separation of activated sludge from a treated effluent is absolutely dependent of the flocculent nature of the microbial slurry entering the secondary clarifier. Despite its importance to the overall effectiveness of the activated sludge process, this naturally occurring phenomenon, termed bioflocculation, remains poorly understood. The inability of the wastewater treatment profession to adequately predict the rate and extent of bioflucculation has significance in terms of both economics and pollution control (Parker et al., 1991).