How to Backwash and Clean a Sand Pool Filter

Follow these easy steps to keep your pool filter in tip-top shape all summer long.

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Photo By: Debbie Wolfe

Crystal Clear

Keeping your pool’s filter system in tip-top shape helps keep the water clean and safe for your family and guests. Here’s a step-by-step guide to cleaning a sand pool filter.


Sand Filters

Sand filters are the most common for pools due to their ease of maintenance and cost. But they do need routine cleaning to keep them working properly. Luckily, it’s a simple process that can be done in less than 30 minutes.


When to Clean

It’s time to clean your sand filter when the pressure gauge reads 8 to 10 psi above the starting pressure (the normal psi reading of your clean pool).  It may be necessary to clean the filter before it reaches these pressure levels if you notice your pool water seems cloudy. The process of cleaning a sand filter is called "backwashing." This process is simply reversing the flow of water back through the filter in the opposite direction, sending the dirt in the filter out through a waste hose. 


Turn off Pump

To prevent damage to your pool’s filtration system, turn off the pool pump and power to the pool at the circuit breaker.

Valve Settings

The valve on top of a sand filter has several settings. It is most likely set to FILTER for normal daily operation. Other settings include: backwash, rinse, waste, closed, recirculate, and winter.


Set the Valve 

To clean the filter, move the valve to the BACKWASH setting. Make sure you lay out your waste hose to where you want the water to flow.


Sight Glass

Turn the power back on and run the pump at the BACKWASH setting for about two minutes. Check the water in the sight glass — it will appear cloudy.


Sight Glass: Part 2

As two minutes or so pass, you will see the water in the sight glass become clear. Once this happens, turn off the pump and switch off the power. 



After backwashing your filter, there will be loose sand that will need to resettle in the filter so it doesn’t return to the pool. Set the valve to RINSE. Turn on the power again and run the rinse cycle for one to two minutes.


Waste Setting

This is used to send  the water out of the waste pipe instead of returning it to the pool. It does not send the water through the sand filter. This may be necessary if  you need to lower pool water level or vacuum algae or heavy amounts of dusty, silty debris from your pool. 



The water is flushed directly out to the drain pipe. 

Pump Basket

Don’t forget about the pump basket! Clogged baskets make your pump have to work harder to try to cycle the water.


Clean Pump Basket

To clean, close the skimmer and main drain valves, then shut off the power. Remove pump lid and use a garden hose to wash the basket. Inspect the pump basket for signs of damage and replace basket if needed. Reinstall the lid, set the valve back to FILTER and turn the power back on.


Happy Swimming

Sand filters are perfect, low cost/low maintenance options for many types of pools. A clean filter is necessary to help maintain the highest water quality level so you can safely enjoy your pool.


Next Up

How to Clean Your Vacuum Filters

Seriously, the vacuum filter is one thing you’re probably forgetting.

How to Clean Walls

Get tips for effectively removing dirt, stains and smudges from painted walls without causing streaking or water damage.

How to Clean Grout

Extend the life of your tile and make it look clean by following these tips for removing dirt and grime from grout.

How to Clean Brass

Whether your household furniture or accessories are solid brass or brass-plated, here are cleaning tips for making anything brass bright and shiny again.

How to Clean Copper

Exposure to water and even air can discolor copper or cause it to tarnish. Here are some tips for how to clean copper safely using ingredients commonly found in your kitchen.