How can you backwash a pool with a sand filter?

The correct expression should be how do you back wash a sand filter. sand filters need back washing when the pressure on front of the filter gets too high. This is done by, stopping the pump and swinging the lever on the top of the sand filter to the backwash position, usually the opposite position. Start the pump. Usually there will be a clear buble near the lever, when the unit is on backwash you will see cloudy water rushing around in it , wait until it clears up, stop the pump again. swing the lever to the rinse position. start the pump and let it run for about 30 seconds or until the water in the bubble runs clear again . Stop the pump. return the lever to the filter position and bobs your uncle, done,