The purpose of this study was to investigate whether a neutral model or non-neutral model dominate the formation of a microbial community. The microbial community that was considered was borrowed from the Werner et al. (13) study in 2011. The data included 16S rRNA sequences for nine anaerobic bioreactors treating brewery waste water. A lognormal distribution was used as the non-neutral model for this study. Using QIIME v1.5 (14) and Microsoft Excel, the best fit lognormal distribution was determined for each of the nine facilities. The R squared values were then calculated. For the nine facilities the R squared values ranged between 0.961 and 0.998. Therefore, the microbial communities in the nine facilities fit the non-neutral model, the lognormal distribution, well.