3 Things to Know About When to Backwash a DE Filter

Backwash when the pressure gauge reads 8–10 psi above your clean baseline pressure. Ignore calendar schedules — the gauge is the only reliable signal.

Backwashing too often wastes DE and reduces filtration efficiency. DE filters work best when the grid is fully loaded with DE.

How often you need to backwash varies with water cloudiness, debris load, and pump run time. In heavy swim season it may be every few days; in winter, once a month. Let the gauge decide.