---
title: "What Is Backwash? Pool Glossary | Marina Pool Services"
description: "Backwash means reversing flow through a sand or DE filter to flush out dirt. Plain-English pool glossary from Marina Pool Services in Grapevine, TX."
url: https://marinapool.multisites.ai/glossary/backwash
publisher: Marina Pool Services
phone: +1-817-896-1120
quote: https://marinapool.multisites.ai/contact
---

Equipment

# Backwash

Backwash means reversing flow through a sand or DE filter to flush out dirt.

Backwashing cleans a sand or DE filter. Water runs backward through the media and out the waste line. It carries trapped dirt away.

Backwash when the [pressure gauge](https://marinapool.multisites.ai/glossary/pressure-gauge) rises well above the clean reading. Your filter's manual gives the exact rise. Run it until the sight glass clears, then rinse for as long as the filter manual says. Do not backwash too often, since the dirty layer helps filtering. Check local rules on where backwash water can go. A DE filter needs fresh powder after.

[Marina can helpPool Filter Service & Installation](https://marinapool.multisites.ai/our-services/pool-filter-repair)

## Related terms

-   [Sand filter](https://marinapool.multisites.ai/glossary/sand-filter)
-   [DE filter](https://marinapool.multisites.ai/glossary/de-filter)
-   [Multiport valve](https://marinapool.multisites.ai/glossary/multiport-valve)
-   [Pressure gauge](https://marinapool.multisites.ai/glossary/pressure-gauge)

## Need a hand with your pool?

Call or text and tell us what your pool needs. Estimates are free for qualifying services, and same-day estimates are possible when the schedule allows.

[Call (817) 896-1120](tel:+1-817-896-1120)[Get a quote](https://marinapool.multisites.ai/contact)

![A pool technician working on an equipment pad](https://marinapool.multisites.ai/_astro/technician-equipment-pad.BW5xZMNY_Zum1K5.webp)