How To Prime A Canister Filter? All The Information You Need


If you are new to canister filters, it is likely that the idea of how they work or what type you should buy has been confusing. This article will review everything from filtration steps, best practices for maintenance and more so your home vegetable garden’s water stays clean and green all summer long.

The “how to prime an external aquarium filter” is a very common question that many people have. This article will answer your question and provide you with all the information you need.


A canister filter is an excellent piece of aquarium equipment. However, if it is not primed properly, it might cause problems in your tank.

So we set out on a quest to figure out how to prime a canister filter today.

There are six simple steps to priming a canister filter. Remove the stopper and decrease the water level below the input. After that, drain the water and set up a siphon at the outlet. After draining the output, you switch on the filter.

Now, if you’re interested in learning more, take a few minutes to read on. We’ve gone through all of the stages and considerations associated with priming a canister filter.

So, what exactly are you waiting for? Let’s get started!

Is It Possible to Prime a Canister Filter?

how-to-prime-a-canister-filter-all-the-information-you-3604433 is a good place to start.

Yes, your canister filter can be primed. This holds true for any and all sorts of tanks. Priming a canister filter entails removing air from it. The priming will pump water into your tank since you’re working with a water pump.

A few days ago, I built up a 20-gallon Tetra Aquarium. Despite the fact that I had just received a brand new Tetra Whisper Filter, I primed it right away. Because priming ensures that the whole system is orientated for the tank you’ve created. 

However, if you’ve chosen a canister filter above other options, you’ve done a fantastic job. This is an excellent way to maintain your tank in good condition. 

Let us learn more about the advantages of priming. 

Why Is It Necessary To Prime A Canister?

There are really two advantages to priming a canister filter. They include the total elimination of Bubbles of air as well as the smooth functioning of the filter.

Clogs and obstructions are less likely as a result of this. As a result, your filter will continue to work properly. As a result, maintenance and cleaning will be easier. 

I know that we aquarists are constantly interested in specific details. So, let’s take a look at a few more lines to see how critical priming a canister filter is.

Bubbles of air 

Bubbles of air in a canister filter are not a good sign. Your canister filter will make gurgling noises and it won’t filter right. 

Bubbles of air cause a plethora of issues and can add troubles with the filter. 

Effortless Performance 

On top of that, Bubbles of air cause issues with clogging and blocks. It won’t drag the water through the hoses and block your canister filter. 

You may confirm that the filter is operating properly by priming it. 

How Often Should A Canister Filter Be Primed?

In general, you should prime your canister filter every three to four months. Cleaning the filter is linked to priming. Your canister filter may need to be cleaned depending on the kind of tank you have. After that, priming takes place.  

However, the above-mentioned concerns might occur in the tank owing to improper setup. So, before priming, double-check that your filter is properly configured.


What is the best way to prime a canister filter?

1650339190_444_how-to-prime-a-canister-filter-all-the-information-you-6524260 is a good place to start.

Internal or exterior canister filters are available. The outward one does need priming, while the interior one does not.

Let’s investigate further, shall we?

Internal Canister Filter Priming

I observed that my MarineLand Internal Canister Filter is substantially smaller than its exterior equivalent as soon as I saw it. It dangles into the tank and is completely immersed. When compared to an external canister filter, there are no hoses or pipes. 

Because the internal canister filter is still submerged in the water, it no longer requires priming. Water stays both within and outside the filter, leaving no place for air to enter. 

Filtering With An External Canister

I now prime my Polar Aurora external filter every time I use it. Because priming is mostly linked with external filter cleaning. There are three layers of filter material in every canister filter. Chemical media are located at the bottom, biological media are located in the center, and mechanical media are located on top. 

Activated carbon is used in the chemical media, which removes tiny particles from the water. Algae in the biological medium aid in the digestion and removal of waste from the water. Finally, a coarse layer of mechanical media eliminates big particles and trash. 

After you’ve cleaned them up, you can start priming. This is a pretty simple procedure that will only take you around 5 minutes to complete. All you have to do is follow the easy instructions below. There are simply six simple phases to the procedure:

Step 1: Disconnect the filter.

This is a straightforward procedure. Remove the plug from the external canister filter and turn it off. This is only to eliminate the possibility of electrocution. 

Step 2: Lower the water level in the tank below the input tube.

Lower the water level in the tank for this stage. It must be done such that it is below the input tube’s level.  

Here, a water transfer pump will suffice. We’re doing this to make sure gravity works in our favor when we siphon later.

We’ve also included a list of transfer pumps for your convenience. We don’t want you to wind up spilling water all over your home or depleting it.

So, let’s have a look at the suggestions below. –

Buy Nowhow-to-prime-a-canister-filter-all-the-information-you-5994212how-to-prime-a-canister-filter-all-the-information-you-8125764Trupow Mini Water Transfer Pump (Portable)
Buy Now1650339193_416_how-to-prime-a-canister-filter-all-the-information-you-39759491650339195_103_how-to-prime-a-canister-filter-all-the-information-you-6975554Marine Water Transfer PumpSumpMarine Water Transfer PumpSumpMarine Water Transfer PumpS

Now let’s go on to the following part, where we’ll learn how to drain the output.

Step 3: Dispose of the Waste

Fill a bucket halfway with water and set the output hose inside. Then, on the output pipe, open the valve and drain it entirely. 

As you empty your tank, you should observe trash and particles. If you don’t, you’ve probably exchanged the hoses below by accident. 

Simply repeat the operation from step 2 after picking up the outlet hose to remedy this. To be on the safe side, you may also fill your canister filter with water. 

Step 4: Make a suction cup

Attach a manual siphon to the end of the output pipe for this step. You must ensure that it is safe and secure, with no leaks. Because if air gets into the canister filter, it won’t prime properly.

So, in order to spare you from this type of pain, we’ve compiled a list of manual siphons that you can trust.

Wait after squeezing the siphon a few times. You should hear a bubbling sound in 2 to 3 seconds. This is the sound of water being circulated by gravity within the canister.

The output hose should then be returned to its original location. 

Step 5: Apply a Net to the Output

A tiny net should be placed on the output pipe at this stage. This is only to capture any debris that could have gotten into the hose. 

The following are some screen nets that would be long-lasting for you:

Grab Now1650339196_696_how-to-prime-a-canister-filter-all-the-information-you-33723671650339197_477_how-to-prime-a-canister-filter-all-the-information-you-2574691Aquarium Screen Net Shappy
Grab Now1650339198_61_how-to-prime-a-canister-filter-all-the-information-you-76393761650339200_870_how-to-prime-a-canister-filter-all-the-information-you-9082750Stainless Steel Mesh by LLMENGEN

You may remove the filter once the water has ran for 5 minutes after it has been switched on. 

Step 6: Activate the Filter

The last step is to simply plug in the filter and turn it on. For a few seconds after the filter begins, you should hear bubbling. 

Following that, the water should flow freely. With that, your external canister filter has been effectively primed. 

Canister filters, on the other hand, come in a variety of shapes and sizes. Some offer specific priming choices, while others do not.

So, let’s take a look at some of the most popular canister filter manufacturers and see what to look for.


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1. The top of the lid has a priming button. 2. Remove the filter plug during priming. 3. Depress the button completely. 4. Fill the water canister halfway. 5. When the filter is full, plug it in.


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1. Press the button, turn it all the way down, and turn the filter off. 2. Press the top primer button. 3. Watch for the water to start flowing. 4. If it doesn’t work, follow the six steps outlined in the previous section.


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1. Ensure that the input and output hoses are completely immersed in water. 2. There should be no water in the exterior connection tubes. Drain them into a bucket by using the valves to drain them. 3. Make sure the canister filter isn’t full. 4. Turn off the valve on the lid. 5. Depress the blue primer button all the way to the bottom until water starts to flow. 7. Connect the canister filter and wait for the bubbling sound to cease.


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1. Drain all water from the canister and double-check that it’s empty. 2. Make sure all faucets are turned on. 3. Insert the input tube into the water. 4. Create suction on the output using a siphon. 5. Close the outlet tap after the water has come out of the outlet. 6. Place the outflow tube into the tank and close it. 7. Finally, connect the electricity.


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1. Remove the filter. 2. Check to check whether the stacks are aligned in the filter. 3. If they aren’t, remove them all and align them. 5. Keep the siphon tab pointing downwards and the rubber gaskets in place. 6. To allow water to flow, press the priming button.


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Prices and availability are correct as of the given date/time and are subject to change. This product will be purchased using the pricing and availability information listed on [relevant Amazon Site(s), as applicable] at the time of purchase.

1. Remove the filter. 2. Turn on the input and output valves. 3. To begin the water flowing, press the priming button 5 to 7 times. 4. Hold your breath until the bubbling sound stops.

All of the techniques and directions for the most popular canister filters are included in this article. Let’s move on to other issues.

What Should You Do If Your Canister Filter Isn’t Priming?

canister-filter-1-1950215 is a good place to start.

Don’t worry if your canister won’t prime. All you have to do now is find out what the issue is and then fix it. So, when I see that my canister filter isn’t priming, I consider the following factors.

If the canister filter isn’t priming, it’s due to loops, fungus, or trapped Bubbles of air. These disrupt the flow of water and prevent proper priming. However, by cutting extra loops, cleaning the fungus, and tilting, these issues can be resolved. 

These problems might occur in the hoses or in the canister filter itself. Continue reading to learn about each of these difficulties one by one. 

Here are some of the most typical concerns that aquarium owners confront while priming their tanks:

Hoses with too many loops

The hoses connect your external canister filter to your aquarium. From the tank to the canister, these hoses normally have to travel a lengthy distance. Because the filter is kept below the aquarium in a specified area, such as a cabinet, this is the case.

You need to make sure that the input and output hoses are kept short and straight. That’s why I prefer Penn-Plax CCF201 Cascade Black Hose. This lets water flow smoothly and prevents chances of Bubbles of air. 

Otherwise, if your hoses have too many loops and bends, the water won’t flow smoothly. They can trap Bubbles of air which then will then cause issues with priming.

This problem may be detected by observing the water flow during priming. Your water should not flow smoothly and should stagger. A strange bubbling sound may also be heard. These are indicators that something isn’t right. 


This has a very easy solution. Your tank needs to be repositioned, and the surplus pipe has to be chopped down. Make sure there’s no more than 1.5 meters between the tank and the canister. 

Now is the time to be cautious while cutting pipelines. Use a PVC ratchet cutter if you want to be safe. The following are some of the suggested cutters:

Choose it right now.1650339217_934_how-to-prime-a-canister-filter-all-the-information-you-24958521650339218_412_how-to-prime-a-canister-filter-all-the-information-you-4016171Tube & Pipe Cutter with Zantle Ratchet
Choose it right now.1650339219_867_how-to-prime-a-canister-filter-all-the-information-you-70732151650339220_312_how-to-prime-a-canister-filter-all-the-information-you-4375908DEWILL PVC Cutter and Ratchet-type Pipe

To complete the task, you may use any of the cutters.

After you’ve trimmed the surplus pipe, ensure sure the hoses are secured to the tank vertically. During draining and priming, gravity will work in your advantage.

Also, for this work, Votmell Teflon Tape is recommended since it is waterproof. Also, make sure you don’t cut any holes in the material.

The Fungus and Algae Fight 

Inside the tank, algae blooming on rocks looks fantastic, but it causes problems in the filter. Fungal spores and algae might accumulate in the hoses and canister because to debris in the water. As the fungus spreads, it might block the hoses and upset the filter media’s balance. 

This implies that your water will seem unclean even if the filter is turned on. Additionally, the water flow in your hoses will be disturbed once again. This manner, you won’t have the difficulty of a steady water flow during priming. 


This problem has an easy solution. Remove the hoses and thoroughly clean them using pipe cleaners. Desin Nylon Pipe Tube Cleaner is my go-to cleaner. This brush set aids in the removal of spores, algae, and deposits from inside the pipes. 

Following that, you must clean the filters. Open your canister filters and immerse them in water for a few minutes. Look for spores or signs of fungal development in the biological medium. If you do, it’s a good idea to switch it.

You may replace your biological media with any of the suggested filter media listed below:

PriceImageProductHow’s it doing so far?
Shop Now1650339221_642_how-to-prime-a-canister-filter-all-the-information-you-52386121650339222_604_how-to-prime-a-canister-filter-all-the-information-you-7353885Filter Media Fluval BiomaxAs water travels through, the contact time is optimized.
Shop Now1650339224_28_how-to-prime-a-canister-filter-all-the-information-you-62556021650339225_310_how-to-prime-a-canister-filter-all-the-information-you-8910071Biological Filter Media by EHEIMAllows for extended periods of time between essential maintenance.

Finally, if you’re still worried, change your tank’s water and collect the long-saved spinosad. Your canister filter should prime in no time once all of the components have been cleaned and handled. 

Inlet has a trapped air bubble. 

Any sort of trapped air is problematic, as you can see. It might also be caused by air trapped in the exit hose and pipe. 

What is the purpose of the outlet? 

Simply because the water in the outlet pipe has to work against gravity. This results in the occurrences of trapped Bubbles of air being high. 

A gurgling sound will be heard, as previously stated. Because there is air in the system rather than water, this sound occurs. This produces priming issues later on. 


This is a relatively straightforward procedure. Tilt the filter diagonally to form a 45-degree angle. Then begin the priming procedure. Water should flow more freely and force the air bubble out because of the tilt.

Be cautious and don’t shake the canister. Shaking can lead to more Bubbles of air forming and misaligning the filters inside. This will cause additional trouble with priming and can ruin the filter. 

We’ve summarized everything in the table below to make things easier for you. 

ProblemIdentification markSolution
Hoses with too many loops1. During priming, water does not flow evenly through the pipes. 2. There are gurgling noises.Remove any extra pipework.
Fungus1. Despite the fact that the filter is working well, the water is still unclean.Change the filter material and clean the hoses.
Trapped Bubbles of air1. The water does not flow freely. 2. Sounds of gurglingStraighten out loops in pipes by tilting the filter diagonally by 45°.

Now that it’s out of the way, let’s move on.

What Is The Best Way To Start A Canister Filter Without Priming It?

canister-filter-3542261 Source:

It is, nevertheless, feasible to start a canister filter without priming it. You may utilize the auto-priming button found on many canister filters. This function will automatically prime it for you. 

There is, however, a way out if yours doesn’t or you don’t want to utilize it.

To get your canister filter up and running without priming, follow these four easy steps. Let’s take a look at them one by one. 

Fill the Inlet Tube in Step 1

To begin, unplug the filter. Fill the input tube entirely after that. Check to see that the valves are fully closed. Air will enter the tube via leaks. 

If you want, you can tilt the canister diagonally. This way the filling up tube will push the Bubbles of air out. 

Place your thumb over the pipe in step two.

Place your thumb on the aperture of the intake tube once it is filled. In priming, this is effectively the siphon section. 

The pressure of water within the tube is maintained by inserting your thumb inside the tube. If you don’t have a siphon, this easy hack eliminates the need to purchase one. 

Step 3: Insert the inlet tube into the tank.

Lower the input pipe into the tank while maintaining your thumb on it. Ensure that no water spills out at this point, since this might cause air to get trapped. 

Release your thumb after the inlet pipe is fully immersed in the water. This will aid in the equalization of water pressure on both sides. 

Step 4: Plug In The Filter And Open The Valves

Simply open the valves and insert the filter in as the last step. When you open the intake and output valves, gravity and pressure compel water to flow. 

This water will flow through the exit, bringing the water pressure back to normal. The water primes itself as it surges forth. 

You may, however, purchase a self-priming canister, such as the Eheim 6666 Pro 4+ Canister Filter, if you choose. These are easy to use and will do the task. After all of that, we’ve covered all there is to know about priming a canister filter. We’re on the verge of crossing the finish line. 


What is the best way to tell whether my canister filter is working?

Check to check whether water is flowing out of the outlet. Many canister filters also produce an apparent gentle ripple. Your canister filter is operating if these signals are present. 

I’m not sure what to put in my canister filter.

At the bottom, look for activated carbon. This is the chemical environment. Add biological media of your choosing on top of it. Finally, add the mechanical media on the top. Wool, filter floss, or a filter pad may all be used. 

How long does a canister filter take to cycle?

It might take anything from 2 to 6 weeks for a canister filter to cycle. It will take two weeks if you have a tiny tank of less than 30 gallons. It will take longer if your tank is bigger and has more activity. 


That’s all there is to it! You’ve learned how to prime a canister filter now. Your canister filter should be primed and working well in 6 simple steps and a little physics.

We wish you success in your priming endeavors. Please leave a comment below if our advise and recommendations were helpful. We’d love to hear what you have to say!

The “canister filter intake and output placement” is a question that has been asked before. The article will give you all the information you need on how to prime a canister filter.

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