The factors affecting algae cells removal by coagulation–flotation–filtration processes were investigated. Differing from previous studies, which mainly focused on optimizing water treatment processes to enhance algae cells removal, this study paid more attention to the effect of algae population characteristics on their removal efficiency during conventional water treatment processes. The results showed that the size, shape, surface structures and the activity of algae cells affected the algal removal efficiency. The higher extent of algae species diversity makes it easier for coagulation–flotation–filtration processes to remove algae. Flotation–filtration processes are used extensively for the treatment of impounded waters either high in colour, or with a high concentration of algae. A major limitation of Flotation–filtration, however, is the conjunction with wholly separate filtration systems. Use of wholly separate filtration systems exacerbates such problems. A variety of techniques has been developed for optimizing water treatment processes to enhance algae cells removal. A pilot plant, containing both the flotation means and the filtration means were developed.