Activated carbon filters are very important for any water or waste water treatment plants like absorbision of smell, excess gas and color, chlorine level etc. A Multi-media water filter systems are used for longer time periods before backwashing is required as the bed can hold more turbidity. Trapping and holding of turbidity takes place throughout the entire bed depth instead of the top one or two inches.
Suitability of multi-media filtration is much better for use in a closed pressure tank since the subsequent breakthrough of turbidity and cracking of the bed virtually eliminates and there is hardly required any visual inspection. Using the pressure tanks is of an obvious advantage than using the open basins or filters for point-of-use filtration and it could also be of importance in small community water supplies filtration. Usage of small diameter tanks with equal or better results also allow the more rapid filtration flow rates in multi-media filtration.