How Often To Clean Canister Filters: Simply Explained

No matter what pet you have, you have to ensure the environment is safe for them to thrive in. That is especially important when it comes to your aquarium. Your fish and plants in the aquarium depend on you to be able to maintain the optimal conditions for them to be able to survive. A very important part of that process is the filtration, and for that you need to know all about cleaning your canister filter! That’s why we have written this article, so that you can go into these processes with all the information at your disposal.

The reason that there are separate articles written on this exact topic is because of how opinionated the answers for this question are. You can not find an exact perfect timeframe for which cleaning out your canister filter. However, it is quite important to do so, for the health of your filter and the ecosystem of your aquarium as well, even if you have the best canister filter out there!

So, how do you go about it if there is no actual answer? Well, if you are looking into getting a canister filter, you should know that they are for people with at least some experience in aquarium maintenance. You will find that when comparing canister filters to power filters, the latter are much more easier to deal with. The plus side for canister filters is that they are much more efficient and reliable when compared to power filters.

Make sure to always look into the manufacturer’s instruction when it comes to the maintenance of your canister filter. They will provide you with an approximate time period for when you should have your filter cleaned. However, you need to factor in with your own expertise as well. You will want your aquarium to look a certain way; clean, no foggy water, etc. So, if you notice anything abnormal forming within your aquarium, it is safe to say that the canister filter is not working optimally, and needs to be cleaned out. 

If the quality of your aquarium water has depleted, then you can be sure that the filter needs to be cleaned out. This is the best way to know if it requires cleaning, as fixed schedules are really not the best way to determine these things. Another helpful tip you could use is that it is best to separate the filter cleaning process and water change process. This way, there won’t be two big changes happening within your tank at the same time.

How Often Should I Change Canister Filter Media?

Canister filters have various processes going on within them, one of which is the filtration media. An example of such filtration media for biological filtration: ceramic rings.  These are the media that make the canister filter carry out its important tasks of filtration, and making sure that all the gunk, debris and chemicals are filtered out, before the water reenters the tank again. 

In cases of using activated carbon in your filter, it is best to change it out on a weekly basis, or washing it biweekly, if you plan to use it longer. There are different time periods for the different types of filter media, but you it is best to keep your own schedule in order to avoid any sudden issue. 

However, it is key to remember that only the carbon-based media require frequent replacing.

Cleaning A Canister Filter

While it is important to know when to clean a canister filter, it is best to first familiarize yourself with how to do it! We’ll guide you with a step by step process on getting it done, and also leave visual aid in order to ensure you understand it 100%. Let’s get into it!

  • First, you’ll need the right tools with you to ensure you can get the cleaning done swiftly and properly. Grab yourself a toothbrush, high-pressure water hose, q-tip (preferably multiple), towel, appropriate working area, additional bucket of aquarium water and a scrubbing pad.

  • Now, to the actual process. With all electrical tools, the first step is to ensure you have turned everything off, in this case, the filter itself. Turn off the power for the filter, and take a look at the outflow tube to make sure it does not have any water coming out.

    After turning the filter off, turn off the horizontal shut off valves, which will prevent water from spilling.

  • After this, you’ll want to move your filter to your cleaning area. Remember that high-pressure water hose we mentioned? You’ll be using that to clean out the insides.

  • After this, you have to disassemble the canister filter to clean it properly. There is most likely going to be a spillage of water, so make sure to have that towel prepared.

    One key thing to remember here is that the tray that holds your biological filtration media needs to remain in some aquarium water. This is where that additional bucket of some aquarium water comes into play. That will allow for the beneficial bacteria to remain alive on the filter media.

  • You then have to clean the impeller, which is placed inside the motor housing. Once you have carefully removed it from the machine, make sure to be extremely careful with it since it is quite fragile. There will most likely be some gunk stuck on it, so gently clean it with the toothbrush.

    If you do end up accidentally breaking something, do not worry since the replacements are quite easy to find in aquarium or fish stores.

    You’ll also need to clean the hole that the impeller sits in, and this will require an even softer touch, for which the q-tip will be necessary. Only one will do the job, but we mentioned you can get multiple since some people like to be thorough with it. We do too!

  • Once you’re done with everything, make sure to take the biological filter tray out, and be fast with your next tasks! While you keep this tray aside, use the water hose to completely spray your canister filter, and ensure that all the water has now fallen out of the filter. This process should remove all of the debris, algae, etc. out of your water filter and will make it clean. After this, wipe it down.

  • After you are finished cleaning, make sure to have everything back the way it was. Be gentle with it still. After you have set it up, allow the canister filter to sit in another bucket of aquarium water so that it can become familiar with the water again. Once it has, plug it back in, and set it up as before.


How often should you clean a canister filter?

A: There isn’t any specific timeframe for this, but it depends on your understanding of your aquarium. If you start seeing any buildup of foggy water or algae in your tank, it means that the filter is not doing its job, and needs to be cleaned ASAP.

How often do you change media in your canister filter?

A: Every month you should be changing your filter media. In between that, you should also schedule some time to clean it out in order to maintain optimization. For activated carbon media, you might need to do it weekly.

How long can a canister filter be off?

A: It can be kept turned off for a maximum of 24 hours. Since the helpful bacteria needed for the ecology of your tank is still in there, you will need to ensure that they can survive. With the lack of oxygen, they will not survive for long, and will decay soon causing a horrible smell.

The Takeaway

Hopefully you have learned how often to clean your canister filter, and can now routinely do it with your own schedule. If you’re still a bit unclear, do not worry as practice makes perfect! Once you get the hang of this machine and its workings, you will find it quite easy to maneuver yourself when it comes to canister filters. Good luck with getting it done right!

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