Slow Sand Filter (SSF) technology is widely used for treating raw water to make it potable. The most commonly used SSF is the down flow technology. Regular filter-cleaning here is a tedious and hard manual work.
By reversing the water flow into an up flow, water head loss is minimized, yet filtration quality remains. Moreover, the filter- cleaning process becomes much easier and quicker by just creating a backwashing flow. It is done by opening the drain plug.