![Sand filter for septic tank. A newly installed sand and gravel filter showing the layout of the pipes, plastic membrane and | CanStock Sand filter for septic tank. A newly installed sand and gravel filter showing the layout of the pipes, plastic membrane and | CanStock](https://cdn.w600.comps.canstockphoto.com/sand-filter-for-septic-tank-stock-photography_csp8388120.jpg)
Sand filter for septic tank. A newly installed sand and gravel filter showing the layout of the pipes, plastic membrane and | CanStock
![Raking the sand in a gravel and sand filter bed for a septic tank installation showing the uncut plastic liner and 4000 litre septic tank sufficient Stock Photo - Alamy Raking the sand in a gravel and sand filter bed for a septic tank installation showing the uncut plastic liner and 4000 litre septic tank sufficient Stock Photo - Alamy](https://c8.alamy.com/comp/KC6FX9/raking-the-sand-in-a-gravel-and-sand-filter-bed-for-a-septic-tank-KC6FX9.jpg)
Raking the sand in a gravel and sand filter bed for a septic tank installation showing the uncut plastic liner and 4000 litre septic tank sufficient Stock Photo - Alamy
![Aerial view of a new septic tank and filter bed being installed showing the position of the pipes in the gravel and sand filter bed, the filters and Stock Photo - Alamy Aerial view of a new septic tank and filter bed being installed showing the position of the pipes in the gravel and sand filter bed, the filters and Stock Photo - Alamy](https://c8.alamy.com/comp/KC6FH3/aerial-view-of-a-new-septic-tank-and-filter-bed-being-installed-showing-KC6FH3.jpg)