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How To Clean A Pool Filter?

Cleanliness is next to godliness and learning how to clean a pool filter is a massive part of making a swimming pool feel like heaven. No one wants to get into murky water, and a lot of the time, this is down to the filter. A cartridge has a certain lifespan but as long as it is within this time, there is no reason why it shouldn’t do its job.

To help give it the best chance possible of making the water as tempting as it usually is, we are going to look at how to clean the pool filter.

The Type of Filter Makes A Difference

That’s the thing about filters, the filter system may be different so the method of cleaning a pool filter can vary. But don’t fret, we have you covered. We’re going to look at each type including sand, cartridges, diatomaceous earth (D.E). None of these are overly complicated, but there are some important steps to remember.

How To Clean A Cartridge Pool Filter

Let’s start with the most common type. Mainly because it is the most likely type that people want to know about, but also because it is the easiest to clean. For most systems, the process is as simple as pulling the cartridge out, rinsing it off, and placing it back.

To go into more detail, and do it properly, follow these steps:

Gather The Equipment

You don’t need a lot, but a hose with a spray nozzle and some filter cleaner is a must, as is a bucket. Other items you might need to keep somewhere to hand include common parts that become damaged and need replacing. These include replacement cartridges and a replacement O-ring, and lubricant.

Cleaning The Cartridge Filter

  • As with many tasks around the pool, it all starts with switching the pump and filter system off. This is for the safety of you and the pool as it helps prevent damage from trapped air.
  • Speaking of, next you will need to turn the air relief valve. This helps move any trapped air that can play havoc with the system. Most often on the top of the filter, turn it slowly but be sure to check in the user manual to be sure that you are turning the correct valve.
  • After this, there may be some sort of clamping system holding the filter in place. Again, check the user manual to ensure you remove them correctly. Then, take the top off the filter.
  • Now you should be able to remove the cartridge with care. Inspect it for damage as any tears or cracks will render it less effective and it should be replaced.
  • If it is still in good condition, it is time to clean it. Use the spray nozzle at the end of the hose to spritz the cartridge. Be mindful of how powerful the spray is as anything too strong could end up damaging the cartridge. If it is particularly dirty, then use a filter cleaner. Anything that is too stubborn to get out using this approach can result in the need to either replace the cartridge or soak it in a bucket of filter cleaner mixed with water.
  • Check the condition of the O-ring on the filter and if necessary, apply lubricant to ensure it is in good condition.
  • Return the clean cartridge to the filter.
  • Reattach the top of the filter and the clamps.
  • Turn the pool system back on, opening the air release valve until the water is streaming through constantly, and close the valve again.
  • Check the PSI on the system pressure and make sure it is at a normal reading.
  • Enjoy the clean water.

How To Clean A Sand Pool Filter

There are two ways a sand pool filter needs to be cleaned. The process is different from a cartridge system, but it can be done with minimal fuss once you know what you are doing. If the PSI level is around 10 over what it normally is then you will need to backwash the filter. When the water looks cloudy, you will need to clean the filter.

The good news is that a sand pool filter doesn’t require an in-depth clean as frequently, so around once a year, the following is all that is needed:

Gather The Equipment

There is less gathering required as you will only need a backwash hose and filter cleaner.

Cleaning The Sand Pool Filter

  • It all starts with removing debris from the system. Backwash for up to 5 minutes.
  • Then, turn off the pump before switching the valve to filter. This should be made clear on the valve but in case it isn’t, consult the user manual.
  • Next, remove the lid of the filter. Once off, pour the right amount of sand filter cleaner in being sure to stick to the guidelines of the product.
  • Put the lid back on.
  • Switch the pump on and count around 10-15 seconds. This should give the cleaner enough time to mix into the filter out of the pump.
  • After the 15 seconds max, turn the pump off and keep it off for another 8 hours (it is fine to leave it off overnight if this is easier).
  • After 8 hours, backwash the filter again, and again for up to 5 minutes to dislodge any debris.
  • Then turn the filter back on.

How To Clean A D.E Pool Filter

A blend of the processes of a cartridge and sand pool filter, D.E pools are still unique. Like a sand pool, they require a backwash when the PSI level goes 10 above 10 it’s normal reading. Again, cloudy water can be a sign that the filter needs cleaning. Otherwise, a monthly clean of the filter is good practice.

Gather The Equipment For A Filter Cleaner Approach

There are two methods for cleaning this type of filter so we will start with using a cleaner is more needed for this type of clean so make sure you have a backwash hose, a regular, hose, D.E filter cleaner, a bucket, lubricant, and D.E. powder.

Cleaning The D.E Filter with Filter Cleaner

  • Start by backwashing the filter for up to 5 minutes.
  • Switch the pump off.
  • Open the air relief valve, again consult the user manual if it isn’t obvious where this is located.
  • Remove the plug of the filter tank to drain the water
  • Remove the filter clamps, again consult the user manual if unsure.
  • Remove the filter manifold and the grids.
  • This is where the hose comes in handy – rinse the filter
  • Spray hose the manifold and the grids, they may be riddled with debris in which case they will need a more thorough clean.
  • If more dirty than usual, apply a D.E filter cleaner and rinse
  • Some manifolds get particlarly¬†dirty. This can be where soaking it in a solution of muriatic acid. This will require safety equipment such as goggles and proper gloves that can protect against acid.
  • Return the grids
  • Add D.E. powder into the filter according to the directions of the brand and the manual of the filter.
  • Next its time to prime the pump
  • Then, remove the lid of the strainer basket
  • Fill the strainer basket with water and make sure some water runs through the line
  • Check on the O-ring. If it is in good condition, lubricate it to keep it that way. If damaged, this is a good opportunity to replace it.
  • Reattach the filter lid and secure the clamps again
  • Next, open the air relief valve and let any excess air filter out
  • Switch the pool pump back on and when the water starts moving through, turn the air valve back off
  • Now you will want to make a D.E powder mixture, mix it with water to make the right consistency, and pour it into the pool skimmer as long as the pump is running.
  • Ensure the pump runs until the D.E solution has had a chance to cover the grids, around half an hour should do it.

How Often Should You Clean A Pool Filter?

This varies depending on the type of system you have but the most frequent is with a cartridge filter. This needs to be cleaned approximately every couple of weeks with a deeper clean with a filter cleaner once a month.

For a sand filter, a monthly clean should be enough. However, it is also a good idea to keep an eye on the PSI level of the pressure gauge. When this approaches around 10 PSI over the regular level, it is time to clean that filter.

A D.E pool filter requires the same attention as a sand filter. Look out for the pressure gauge reaching 10 over again, and clean it monthly. Each time it is cleaned, add fresh D.E solution to ensure the water is as clear and clean as possible.

What Is The Easiest Type Of Filter To Clean?

There is a reason why cartridge filters are so common but although they are the easiest to clean filter wise, the overall maintenance can be a little more time consuming than the others. Once you have cleaned a pool filter a couple of times, it becomes an easy task.

How Long Does It Take To Clean A Pool Filter?

For the most part, this task shouldn’t take longer than half an hour when you know what you’re doing. Of course, when it comes to soaking parts this can be done overnight so the process takes longer but most of this does not need your attention again until it is ready to reinstall into the filter.

How Long Does A Pool Filter Last?

The good news is that most quality pool filter cartridges up to 2-3 years if maintained properly. Of course, the more the pool is used the more wear and tear there will be. Pollutants in the water such as sunscreen, hair care products, and other chemicals will take ther toll eventually. With proper maintenance and cleaning, you can expect to get the maximum lifespan out of a filter cartridge though.

Should I Replace My Pool Filter Cartridge?

Although they are inexpensive, the cost of pool maintenance can start to add up if you replace the filter cartridge every time you go to clean. This is unnecessary unless there are noticeable signs of damage. So, any tears or cracks in the cartridge are signs that a new one is required, otherwise, keep cleaning, and let it do its job.

What If There Is A Sudden Spike In The PSI?

This is a common sign that the filter is struggling so it is worthy of your attention. The PSI gauge should hover around the same place so when you notice it starting to creep up, keep an eye on it. At 10 over the normal level,  give the filter a quick clean, a hose down should do the trick. If not, a deeper clean may be required such as leaving it to soak in a cleaner solution overnight. When this fails, replacing the cartridge is the next step.

Can I Clean A Pool Filter Myself?

If you have a maintenance team that looks after your pool, then they will usually take care of cleaning the pool filter. It never hurts to ask to be sure. If you find yourself maintaining after the pool then this is not a task that requires a lot of expertise, just a little care, and patience.


Although some are easier to clean than others, it doesn’t take long to learn how to clean a pool filter. A lot of the steps are the same anyway but even with the more complicated filters, it will get easier the more you do it. Good Pool maintenance is key to prolonging the lifespan of all the working parts, as well as making sure the water is clear and clean enough to enjoy. Unless it is the middle of the colder months, you should be spending a lot more time in the pool, than in the pool room cleaning the filter.

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