A Diatomaceous Earth (DE) Filter cleans your pool water by passing the water through a set of normally 8 grids. Each of these grids is covered with a layer of DE powder. If your pools water is not clear and/or your filter's pressure gauge is reading about 10 psi higher than normal, It's time to backwash your filter to strip the current layer of DE power off the grids and replace it with new powder. Although this guide is specific to a Hayward Pro Grid DE Filter, many of its steps are applicable to most DE filters. Note: About once a year you should take the grids out of your DE Filter and clean them more thoroughly. See our guide on "How To Remove and Clean Hayward DE Filter Grids" for more information.
TURN PUMP ON AND BACKWASH - Turn the Pump back on and backwash for 2-3 minutes to strip the old DE Powder and contaminates off the filter grids. The flow of water during a Backwash cycle is reversed from that of the Filter cycle and dirty water and old DE Powder is washed out the waste line. Note: This process will lower your pool's water level slightly. If it started low, you may have to add water to the pool with a garden hose.
TURN PUMP ON AND RINSE - Switch the pump back on for 30 seconds or so to rinse the grids from the normal Filter side of the grids. In this mode, water flow is switch back to flow in the same direction as it would in the Filter mode, except the water and any remaining residue is purged out the waste line.
REPEAT BACKWASH AND RINSE - If it's been awhile since you backwashed your filter, you may want to repeat the Backwash / Rinse cycle again to get any stubborn DE Powder and contaminates out. Repeat steps #3 through #10. If not, continue to the next step.