Learn which plants thrive in your Hardiness Zone with our new interactive map!

How do I Stop a Leak on a Lid for a Pool Sand Filter?

By Justin A. Mann ; Updated September 21, 2017
Keep your pool looking good with a working sand filter.

Sand filters are one type of filter commonly used for swimming pools. Sand filters work by passing pool water through a tank holding sand. The sand cleans the water by catching and filtering out impurities and debris from the water. Sand filters are exposed to high water-pressure and the weight of sand constantly, which can cause problems to occur within the filter. One common problem is a small leak located on the top of the sand filter.

Examine the thin metal band, called a band clamp, around the top of the filter. Use a screwdriver to tighten the band clamp and ensure a leak cannot continue in that area.

Examine the sight glass of the filter. The sight glass is a small clear glass container that is screwed onto the side at the top of the filter. For leaks coming from the sight glass, unscrew the sight glass and apply Teflon tape to the grooves of the glass, then screw the sight glass back into place.

Turn off the filter system. Check the dial valve on top of the filter and ensure it is seated firmly in place. Poor positioning of the valve results in pinching of the o-ring underneath, which allows water to escape the filter. Try moving the dial valve to a few different settings, and then back to default.

Check the backwash line of the filter for leaks. Ensure the small clamp over the backwash line is tight. When not using a backwash hose, insert a plug into the backwash line to prevent leaks.


Things You Will Need

  • Screwdriver


  • Backwash your filter weekly to avoid most common filter problems. To backwash, run the filter in reverse and dump the waste water.

About the Author


Justin A. Mann has been a freelance writer since 2007. Mann is experienced with computers and all things relating to swimming pools, and he uses his knowledge in these fields to write articles for various websites. Mann is an English major at East Central University.