Many people around the world have swimming pools and love the amount of time to relax they get because of their water features.
However, a lot of these pool owners don’t realize how much maintenance and different features are required to keep them from becoming dirty and unsafe to use.
Most people would’ve heard about swimming pool filters and the significance they have to keep a swimming pool safe for use.
We have a guide here for you which helps you to understand how important swimming pool filters (see also ‘How To Read Your Pool Filter Pressure Gauge‘) are, what they do, and how to backwash them to keep them functioning to their best capacity.
At the end of the day, what’s the point in having a swimming pool if you can’t use it safely?
Table of Contents
What Is A Swimming Pool Filter?
A swimming pool filter is an essential part of any swimming pool system.
It keeps your pool clean and safe by filtering out debris, dirt, pathogens, chemicals, and other impurities that could harm you or your family members.
The first thing you should know before using this device is that there are two types of pool filters in existence: cartridge-type filter and sand filter.
Sand filters (see also ‘Sand Filters Vs Cartridge Filters‘) require more maintenance since they need to be cleaned regularly while cartridge filters only need to be cleaned once every 3-4 weeks.
These days, most modern cartridge-type filters come with built-in pumps so that you won’t have to worry about pumping and cleaning manually.
When properly maintained, these filters will last you many years without fail.
How Does A Swimming Pool Filter Work?

The function of a swimming pool filter is simple yet very complex at the same time. First off, let’s talk about the materials used in making one.
They are made up of polypropylene (PP) fibers, ceramic media, and a frame that holds everything together.
These components help trap all kinds of particles and make sure that they stay away from the water.
As mentioned earlier, when the filter gets clogged with debris on its surface, the water flow inside the filter becomes restricted.
This restricts the amount of water that flows through the filter, and eventually causes the pressure within the filter to drop.
That means that the filter needs to be removed and cleaned.
These filters work by passing the water through the filter material where the debris is trapped.
If you want to learn more about the best swimming pool filtration systems, then read our article right now!
Why Should I Backwash My Swimming Pool Filter?
Backwashing is the process of removing solid matter from the filter. It involves using either a vacuum or a chemical solution to clean out the debris.
Some swimmers prefer to go with the latter method as it doesn’t involve any chemicals that might affect the quality of their water.
If your filter has been used for long enough, it may start getting clogged with some hard stuff like calcium carbonate deposits.
You can easily remove those things by backwashing. In case you’re not aware, there are several methods of doing this. Here are just three of them.
You need to do this otherwise your filter won’t work nearly as well as you need it to.
Because of how important filters are to keeping your pool clean, you need to ensure that you backwash your pool whenever you see fit.
How Often Should I Backwash My Pool Filter?
One of the biggest questions that people ask themselves when they get into the world of swimming pools is “how often should I backwash my pool filter?”.
Well, we’ve got good news for you because it depends entirely on what type of filter you own.
Let’s take a look at both the cartridge-style and sand-style filters separately.
Sand Filters
This kind of filter works differently compared to cartridge filters.
Unlike the former, which traps a lot of debris inside its media, a sand filter relies on a layer of sand to capture fine particles.
When it comes to sand filters, you’ll usually find yourself having to change the sand layer after every few months.
If you don’t do this, the filter will quickly become full of dirt and debris.
Cartridge Filters
Unlike sand filters, cartridge-style filters use a different approach.
The main difference between the two lies in the fact that while sand filters rely on a single layer of sand to catch particles, cartridge filters are equipped with multiple layers of fiber.
That being said, it still takes a certain number of changes before the dust and other small particles settle down and build up inside the features.
So, if you want to protect your filter from becoming too full, you need to backwash it regularly.
How To Backwash My Sand Filter

Step 1 – Deactivate Your Pool Equipment
Firstly, you need to turn off the water pump by accessing the power switch. If you like, you can also do this through the circuit breaker box.
Make sure you don’t make any changes to the modes activated on the water valve alongside your pump because you might cause damage to certain features like the spider gasket.
Step 2 – Change The Sand Filter Setting
Here you’ll need to make sure that the sand filter (see also ‘How To Connect Hoses To Your Sand Filter‘) valve is in the backwash position, making sure that the handle won’t budge.
If it isn’t locked in place then it can be moved, which will slow down your cleaning process.
Step 3 – Turn The Pump Back On
Turn the pump back on in the same place that you turned it off earlier, making sure that the backwash position is still active on your sand filter valve.
Backwash the water for 2 minutes until it is see-through when you look at it through the sight glass. Once this is done, turn the pump back off.
Step 4 – Rinsing Time
Now change the filter valve setting to rinse and once again make sure that the handle doesn’t slip.
You need to make sure that this is locked in. Turn the pump back on and rinse for around half a minute to a minute.
Once again, the water needs to be clear for you to have done this effectively. Turn the pump off again once this is done.
Step 5 – Close The Skimmer Valves
Doing this will make sure that water won’t enter the filter, coming from the swimming pool.
Once you’ve done this, empty the skimmer basket. This is fairly easy, which will allow you to clean out the hair catcher as well.
Step 6 – Return To Normal!
Once you’ve done all of this, you should be able to go back to normal and resume using the swimming pool as usual!
Not too tough once you know where to start.
Can You Backwash A Cartridge Filter?
The simple answer is no. This is because these models of swimming pool filters don’t allow backwashing, unlike sand filters.
However, you can still take care of them without having to bother about the backwashing process, as long as you’re careful enough not to damage the filter in any way.
How To Clean A Cartridge Filter
This is a fairly easy process, which involves a few different things. Open up the filter and take the cartridge out from its hiding place.
You’ll need to spray this cartridge down with a garden hose and rinse it to ensure that any debris or dirt is removed from the cartridge.
Repeat this process once every month or so to ensure that there’s no build-up of external materials inside of the cartridge.
This will keep your filter working to the best of its ability.
How To Tell When My Filter Needs Cleaning
If you notice that your filter isn’t looking quite as new anymore, then you should contact your local swimming pool service company.
They are the ones who will be able to tell if your filter needs cleaning or not.
If they think that your filter needs some help, then they will be able to give you an idea of how often you need to perform this process.
You can also notice your filter needs to change when the water starts to get dirty.
Your filter is there to stop this from happening, so the simple observation is that if the water is dirty, then the filter isn’t working properly and it’s worth looking at.
How Often Should I Perform Backwashing?
You should consider performing backwashing as soon as you notice any signs of dirt or debris building up within your filter.
For instance, if you notice that the flow rate is decreasing then you should perform a backwash.
It is important to remember that you shouldn’t wait much longer than 24 hours after doing a backwash before you do another one just to double-check that your filter is working properly.
After that, you should be good to go for a month or two.
Benefits Of Having A Working Swimming Pool Filter System
Many benefits come with having a working filter system installed in your swimming pool.
One of those benefits is keeping your swimming pool free from any debris or dirt particles.
Another benefit is that your filter will prevent algae from growing in your swimming pool. Algae is known for being very harmful to swimmers.
It can cause skin infections, eye problems, respiratory issues, and lots of other more serious health problems down the line.
So, what exactly are algae? Well, it’s a type of plant that grows in water bodies such as ponds and lakes.
It lives by absorbing sunlight through photosynthesis, but it does this to produce energy.
In other words, it uses sunlight to produce food for itself.
Most people refer to this as green slime, since most types of algae appear green due to their pigment content. Get rid as soon as you can!
Final Thoughts
You should now be able to clean your pool filter with relative ease and make sure that your swimming pool remains clean and safe for use.
Frequent maintenance and cleaning of your pool filters (see also ‘ How Much DE To Add To Your Pool Filter?’ ) are essential to staying safe and need to be done, even though we know it can be frustrating at times.
However, any swimming pool owner will tell you that they expected to have some sort of upkeep before they installed their water feature.
If you don’t feel confident enough to clean your filters without damaging your filter systems then it’s always best to contact a professional to make sure that your filters get cleaned without stress and anxiety.
As long as they get seen to, you’re on the right track. As we previously mentioned, there’s no point in having a swimming pool if you can’t use it!