It is well recognized that the deposit of excess food in the sediment results in an anaerobic digestion process that produces NH3 and H2S that diffuse into the water column. Aeration in the water column helps the bacterial population to convert NH3 to NO3 and H2S to SO However, more PSB were found in the water column; this indicated that the sulfide (S 2-) produced in the sediment diffused into the water column.