Results showed that the removal increased with an increase in coagulant dosage until it reached an optimum value, the removal started to decrease.This could be attributed by the restabilization of colloidal particulates when coagulants were used at dosages in excess of the optimum value (Aygun & Yilmaz, 2010). With the addition of larger dosage of the coagulant, the surface charge of the particles gets reversed due to continued adsorption of mono- and polynuclear hydrolysis species of coagulant. As the colloidal particles become positively charged, they cannot be removed by perikinetic flocculation (Verma,
Prasad, & Mishra, 2010).