How to Clean Pool Filter Cartridges: What You Need to Know

  • By: John Parker
  • Last Updated: November 24, 2022

A clean and healthy pool filter is vital for ensuring the pool water is free from dirt and debris. If you have a dirty filter then trying to clean a pool will be much more difficult.

Cleaning your cartridge filter for the first time may seem daunting, but you’ll be pleased to know it’s not as scary as it sounds.

To find out more about pool filter cartridges and how to clean them the right way, then keep reading!

dirty pool filter cartridges
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Table of Contents

Why do you clean pool filters?

Before we dive in, you may be wondering why a pool cartridge filter needs cleaning up in the first place.

Pool filters work to collect small pieces of dirt and debris that move through the water from people, animals, leaves, etc. Traces of body oils, calcium and even insects often clog up the filter leaving it unable to do its job.

Cleaning the filter every once in a while is all part and parcel of basic pool maintenance.

Cleaning a pool cartridge filter: A mini guide

Our 8-step guide below will tell you all you need to know about how to clean the filter cartridge.

Step 1: Turn off the filtration system

Turning the pool pump and filtration system off is essential when dealing with the inner workings of a swimming pool. This avoids damage to the equipment and yourself.

You will now need to turn the air relief valve to ‘open’ and expel the air from the filter tank. It is important that you do not open the filter tank until there is no air left inside.

Step 2: Open up the filter tank

Removing the filter tank lid is pretty straightforward. Most are designed using an O-ring which is removed by pressing on the ‘release’ buttons and twisting counter-clockwise.

If you are struggling, you can always resort to the filter owner’s manual (if you still have one!).

Step 3: Remove the cartridge

Once the lid has been removed, you can reach into the tank and pull out the cartridge filter. The way this happens depends on the model of your cartridge. Some models of cartridge filters are designed with one large attachment, but others may come apart separately once removed from the filter housing.

Again, you may need to take a look at the manufacturer’s manual which will advise you on the best way to take it out.

How to Clean a Pool Filter Cartridge

Step 4: Check for any damage

Once the filter cartridge is safely removed, you can check for any wear and tear. There may be small cracks or tears in the material.

If you do stumble upon even a tiny piercing or crack, this can impact the efficiency of the filter so we recommend purchasing a new one. Cartridge filters generally last between 3 and 5 years before they need to be replaced.

Step 5: Remove dirt or debris

A garden hose is the perfect piece of equipment for this job. The best way to clean away the dirt is to start at the top and spray down to the bottom. Then flip the cartridge around and repeat. A hose with a powerful nozzle attachment is ideal for this kind of filter cleaning job.

Note: There are a few filter cleaning products on the market that attach to a garden hose and allow the water to get inside the filter pleats easily to help clean more thoroughly. One of the most popular is the Katikies Cartridge Filter Cleaner, which is available on Amazon.

katikies Pool Filter Cartridge Cleaner Tool,Removes Leaves, Debris and Dirt in Seconds from Your Pool,Spa or Hot Tub Filter Cartridge

Step 6: Time to deep clean

Hosing is effective at removing larger pieces of debris and dirt, but a deeper clean using a bit of elbow grease is also needed.

Oils from sunscreen, skin and sweat can be hard to remove, particularly if there is a lot. A generic filter cleaner or pool degreaser will get the job done, both of which can be found in most retail stores. Simply spray the product onto the cartridge filter and leave for a minute or so before rinsing off.

Step 7: Place cartridge back inside

Once you are happy with the way the cartridge looks, you can go ahead and place it back inside the filter tank. Remember to secure the lid before turning the air relief valve to a ‘closed’ position. It is now safe to turn the filtration system back on.

Step 8: Check filter air pressure

To make sure everything is in order, check the air pressure by twisting the air relief valve open slightly to release any excess air. When the water begins to spray out in a steady stream, you can turn it back to a closed position.

Pool filter cartridge cleaning tips

We’ve put together some tips that may come in handy, particularly if this is your first time cleaning your cartridge filter.

  1. Always resort to the manufacturer’s manual for guidance before tampering with pool equipment. Following instructions is key if you want to avoid any damage.
  2. Pool filters only become a problem if you don’t tend to them. Therefore it is wise to manually check the pool chemistry at least every two weeks during the colder months and once a day when the pool is in use.
  3. You don’t need to clean your cartridge filter every day. Doing this can do more harm than good.
  4. Do not use a pressure washer to clean your cartridge filter. This can damage the material which will reduce its efficacy. The filter does not need to look brand new before it goes back into the filter tank. As long as the majority of the dirt is removed, you’re good to go!
  5. Ideally, the pressure gauge should give a reading of 10-15 PSI. If it doesn’t look right, take a look at the manufacturer’s instructions, or contact a professional.

XtremepowerUS Pro-Series Pool Cartridge Filter In-Ground Swimming Pool and Spa Pool Filter System w/ 4 Filter 425 sq ft Inground

Cleaning your pool filter cartridge with muriatic acid

If your pool filter is heavily coated with grease and grime, you may need something a little harsher than water from the garden hose. Remember, muriatic acid is an acid, and as such is a chemical that should be used sparingly. You should always wear protective clothing and safety goggles when using this product.

Using muriatic acid

To begin with, you should follow the steps set out to clean your pool filter as normal. Then follow the steps below.

Step 1: Change into protective clothing

If you haven’t already done so, you will now need to put on some protective goggles and acid-resistant gloves. You should also wear a long-sleeved shirt and trousers for extra protection. If acid splashes on the clothes you will end up with holes so ensure that they are dispensable and not your best!

Step 2: Prepare the solution

Dilute the muriatic acid in at least 5 gallons of water. Refer to the instructions on the back of the product for more information on the diluting process.

Step 3: Soak filter

You may now place the filter in the diluted solution and allow it to soak overnight. When removing the filter from the solution, wear your protective gloves and goggles once more.

Pool Maintenance Course

When I first bought my house with a swimming pool, I knew nothing about cleaning and maintaining it. I was recommended Swim University’s Pool Care Handbook and video course so I bought it and have never regretted it.

It was probably the best money I spent that year as I have saved thousands by doing it myself.

How to clean different pool filters

If your pool doesn’t use a cartridge filter, it will use either a sand or a D.E (Diatomaceous Earth) filter. Luckily, we have also taken some time to put together a mini guide for each. Let’s take a look at them!

How to clean a sand pool filter

Sand pool filters are a popular choice amongst pool owners as they are the cheapest option and easy to use. When the pressure gauge reaches between 8 to 10 PSI above the measurement taken when clean, it’s time to think about cleaning the sand filter.

Here’s how to do it.

  1. Begin by backwashing the filter for a few minutes to remove as much dirt and debris as possible.
  2. Again, turn off the pool pump before twisting the valve to ‘Filter’ mode.
  3. Remove the strainer lid and add in some sand filter cleaner.
  4. Replace the strainer lid and turn the pump on for 10 seconds. This allows the sand cleaner to quickly travel from the pump to the filter.
  5. Leave the pump off for around 8 hours, or for best results, leave overnight.
  6. Give the backwash another quick clean before turning the pump and filtration system back on.

Cleaning a D.E. (diatomaceous earth) pool filter

D.E filters are often thought of as the best filter systems. They are capable of capturing and filtering particles as small as 3 microns (one grain of salt is around 90). Good, working D.E filters are long-lasting and easy to clean. Below is a short guide to tell you how to do it.

  1. Start by backwashing the filter for a few minutes before turning the pump off.
  2. It is now time to turn the air relief valve to ‘open’.
  3. Drain the filter tank by removing the drain plug.
  4. Open the filter tank. If you struggle to do so, take a look at the manufacturer’s instructions.
  5. Remove the grids and the filter manifold. You can also use a garden hose to clean out the tank itself.
  6. Clean both the manifold and the grids with a hose, filter cleaner, or a diluted muriatic acid solution.
  7. Finish by placing the manifold and the grids back inside the filter tank. Once the lid is securely in place, you can turn the filtration system back on.
Pool filter cartridge cleaning tips

FAQs

If we didn’t manage to answer your questions above, our handy FAQ section may be of help.

How to backwash a pool with a cartridge filter

This is simple since you cannot backwash a pool filter that uses cartridges. They are not built to be backwashed and there is unlikely to be that setting available to you anyway. Instead, you have to remove the filters and clean them manually using a garden hose or similar.

Can I use vinegar to clean my pool filter cartridge?

Yes, you can use vinegar as a cleaning solution for your pool filter cartridge. To do this, you will need to dilute one part vinegar to one part water. However, muriatic acid is a much more effective cleanser.

How often does a cartridge pool filter need cleaning?

As mentioned above, there is no need to clean your cartridge filter every day. We recommend removing the filter for a clean every 2 to 6 weeks. This allows the filter to pick up as much dirt and debris as possible for you to remove.

What other solutions can I soak a pool filter in?

You can make your very own solution using good old dish soap. To do this you will need to add a cup of liquid dish soap to at least 5 gallons of water. Then allow your pool filter to soak for as long as you wish.