Fig. 6

FE of E. gracilis was determined at pH 8.5 with and without EDTA. FE, flocculation efficiency; EDTA, ethylene diamine tetraacetic acid. Control A represents a control group at the CPV without EDTA; Control B represents a control group with added EDTA; NS, ** represent p > 0.05, p < 0.01, respectively. The values represent mean ± S.D. n = 3