How often should a pool's sand filter be backwashed?

Backwashing a pool's sand filter is an essential maintenance task that ensures efficient operation and water clarity. The correct frequency for backwashing is determined by monitoring the pressure gauge on the filter. When the pressure increases significantly from the normal operating range, it indicates that the filter media is becoming clogged with debris and dirt. This can lead to reduced water flow and ineffective filtration, making it necessary to backwash.

Backwashing every 4 to 6 weeks is a general guideline, but the actual timing can vary based on pool usage, environmental factors like debris accumulation, and the specific type of filtration system. Regular monitoring of the pressure gauge will provide the best indication of when backwashing is necessary, allowing for a more tailored maintenance schedule that optimizes filter performance and keeps the pool water clean.

The other options suggest either too infrequent or too frequent backwashing, which could lead to inadequate filtration or unnecessary wear on the filter system. Adjusting the backwash frequency based on the pressure gauge ensures that the filter is maintained effectively.