Abstract: Mixed bacterial compositions minimally contain a mixed population of bacteria including at least one species of Nitrosomonas capable of converting ammonia to nitrite, at least one species of Nitrobacter capable of converting nitrite to nitrate, at least one species of Pseudomonas capable of converting nitrate to nitrite and capable of metabolizing urea, and at least one species of Enterobacter capable of metabolizing bacterial waste products and fermenting lactose. The ability of these aforementioned bacteria to metabolize the odor; and partially decompose the waste material producing the odor is enhanced by the addition of an acclimated mixed bacterial culture to the mixed bacterial composition containing the aforementioned species of Nitrosomonas, Nitrobacter, Pseudomonas, and Enterobacter. The acclimated mixed bacterial culture includes at least one and up to four different species or strains of Pseudomonas, at least one species of Acinetobacter, and at least one species of Enterobacter.