Numerous advantages have been reported on PAC (poly aluminum chloride) used as a coagulant over other coagulants such as alum and ferric chloride used in conventional water treatment process with medium and high turbidity levels. These include lower amounts of PACL required specially in removing turbidity. larger floc grain formation. reduced floc sedimentation time. https://www.roneverhart.com/7-Plush-Oswald-Octopus/