Ozone oxidation is influenced by several factors, such as pH and contact time which increase in pH and contact time will be able to increase the pollutants removal [23].Longer contact time will enhance the oxidation reaction, making a larger pollutant removal occurs [3]. [28].The increasing Ozonation time will enhance the colour and COD removal with the ozone dose of 125 mg and ozonation time for 25 minutes can reduce the colour concentration up to 51.3 % and COD by 67 % [48].