2.3. Statistical analysis
One-way ANOVA was used to analyze the differences among wastewater dilutions for different characteristics of the treated water in different set-ups. A Tukey's test was also performed to identify the homogeneous type of the data sets. The relationship between removal rate and WW dilution factor was measured using regression analysis. SPSS® statistical package (Window Version 13.0) and STATISTICA® (Window Version 7) was used for data analysis. All statements reported in this study are at the p < 0.05 levels.