For removal of bacteria -
Slow sand filters are for effective in removal of bacteria. Slow sand filters remove about 99.9- 99.99%.Rapid sand filters remove 98-99% bacterias. Slow sand filters occupy less area,operation is less skilled. Parks textbook of preventive and social medicine.K Park. Edition 23.Pg no: 714.
Rapid sand filter is more effective
Slow sand filter is more effective
Both are equally effective
Rapid sand filter removes 70% bacteria
Environment and health