What is Backwashing a Pool? An Essential Guide

June 24, 2023 by 

If you own a swimming pool, you know the awesome feel it gives on hot summer days. Nothing beats the joy of diving into its cool waters or just chilling on a float, soaking up the sun. But, keeping this watery wonderland dazzling needs care and some insider info. One key bit of pool care is a process called backwashing. You might be scratching your head, wondering, what is backwashing a pool? Let’s jump in and clear things up.

Backwashing is a cleaning trick that sends water flowing backward through your pool filter to clean out the collected gunk, debris, and icky stuff. Regular backwashing is key to keeping your pool looking tip-top and inviting. This post will break down the ‘what’, ‘why’, and ‘how’ of backwashing a pool and share some handy tips for keeping your pool filter unclogged.

What is Backwashing a Pool?

Backwashing is a regular cleaning routine designed to keep your pool filter working great. In simple terms, the procedure involves sending the flow of water through your pool filter in reverse.

How does this go down? It starts with turning your filter’s multi-valve to the ‘backwash’ setting. By doing this, water from your pool is sent through the filter in reverse, washing away any built-up dirt and nasty stuff stuck in the filter stuff.

The filter stuff is the porous material that water passes through as it flows through the filter. It’s usually made from sand, glass beads, or diatomaceous earth (DE), all great at trapping little bits as water flows through.

However, over time, these materials collect junk, potentially slowing the water flow and leading to a murky, unappealing pool. By backwashing, you effectively remove and wash out these impurities, getting your filter back to working great.

Why is Backwashing Important?

So why is backwashing a pool so key? There are a few solid reasons:

  • Making Sure Filtering Works: A clogged filter can’t effectively get rid of dirt and debris, which can leave you with a cloudy or dirty pool — not exactly the stuff of pool parties!
  • Stopping Green Slime: Proper filtering stops the buildup of nutrients that algae need to grow. So, backwashing plays a major part in stopping that unwelcome green look.
  • Keeping Water Clean and Safe: A clean pool is less likely to become a hotspot for bad bacteria or other yucky stuff, making for a safer swim and less risk of catching anything nasty.

How to Backwash Your Pool

Backwashing a pool is pretty straightforward if you stick to these steps:

  1. Find the Multi-Valve: This is usually a round or rectangular valve found near the filter.
  2. Turn the Multi-Valve: Switch it to the ‘backwash’ position to get the water flowing backward.
  3. Get the Pump Going: The water will start flowing through the filter in reverse.
  4. Watch the See-Through Bit: This clear window lets you check out the water as it moves through the filter.
  5. Clean Until Clear: Keep the backwash going until the water in the see-through bit is clear. This might take a few minutes.
  6. Get Settings Back to Normal: Turn off the pump and switch the multi-valve back to the ‘filter’ setting.

Tips for Preventing Clogged Filters

To make your pool care even better, try these tips to avoid clogging your pool filter:

  1. Vacuum Often: Regular vacuuming gets rid of dirt and debris before it can block the filter.
  2. Clean the Filter Lots: Clean your filter often by backwashing or using a filter cleaner.
  3. Get a Good Pool Filter: A top-notch filter will be harder to clog.
  4. Stay Away From Nasty Chemicals: Using too many harsh chemicals can mess up the filter stuff, making it easier to clog.


To answer the question – what is backwashing a pool? – it’s a key part of pool care that keeps your filter in running smoothlyr, stops green stuff, and keeps water spotless and harmless. Regular backwashing is one of the best ways to keep your pool looking its best.

By following these steps and using these helpful tips, you can backwash your pool like a pro. Here’s to loads of happy, easy-going days in your super clear pool!

Remember, a clean pool isn’t just a pretty sight; it’s proof of your hard work in making a healthy and safe swimming spot for everyone. Happy backwashing!