How to install a fish tank filter cartridge? Believe me, it’s one of the simplest things you can do to keep your fish tank running smoothly.
The process of aquarium filtration is done by filtering the water through a series of filter media which traps all impurities before releasing clean water back into the tank.
Filter cartridges help purify aquarium water by absorbing debris and impurities. However, they have a certain service life, after which you need to replace them for optimal benefits.
In this blog post, I’ll tell you how to install a new filter cartridge and get back to enjoying your finned friends! It’s really easy once you know what to do!
But the most straightforward task can become arduous if you don’t know the correct procedure!
Types of Fish Tank Filter Cartridges
I am going to talk about filters that use a cartridge system. This includes:
- Hang On Back (HOB) Power Filters
- Canister Filters
- Internal Air-Powered Filters (Sponge)
- Internal Submersible Filters
- Internal Tetra Filters
Hang On Back (HOB) Power Filters

HOB filters are designed to be hung on the back of a fish tank.
Hanging power filters is one of the most popular for aquariums 10-40 gallons or larger.
They’re compact and easy-to-use equipment consisting of almost everything you need in an aquarium filter.
In HOB (hang-on back) power filters, the pumps draw water into a filter box from the aquarium.
The filter box houses slip-in cartridges that act as a filtering material for fish tank debris and other contaminants to clean it up before returning it to the tank.
Canister Filters

Canister filters are used in medium and large-sized fish tanks. Canisters are placed underneath the aquarium, out of sight.
The water that flows through this filter is filtered by three different types of media: mechanical filtration, chemical filtration, and biological filtration.
High-powered pumps suck the water from inside the tank into these special casings containing all sorts of filter media.
Internal Air-Powered Filters

These aquarium filters are for small tanks that cannot handle an external filter.
They are powered by an air pump. When the air pump is turned on, it creates bubbles that travel up a tube and cause water to flow through the filter media.
This type of filter uses either sponges or other simple materials but provides excellent mechanical and biological filtration.
Internal Submersible Filters

Submersible filters are just like HOBs, but they need to be fully submerged in water.
You attach these filters with suction cups to the aquarium wall and power them with an electric pump. They’re suitable for nano tanks as well as 30-gallon tanks.
Some models of internal submersible filters offer a three-stage filtration system.
How To Install Fish Tank Filter Cartridge For Different Types
Hang On Back (HOB) Power Filters
- Unbox the filter and check if the motor and impeller are in okay condition.
- Rinse the filter media in freshwater thoroughly.
- Install the cartridges and media baskets in their designated places.
- Hang the filter on the back of your tank or securely place it inside.
- Prime the pump with water if needed.
- Turn on the filter.
Once you’ve purchased a filter, the next step is to unbox it and check if all parts are in good condition.
Rinse off any dust accumulated on filters using freshwater before installing them into their designated place inside your tank or the back of your aquarium.
A HOB filter is hung on the back of an aquarium. Before installing, ensure there’s enough space and that it can’t tilt too much, or else water might splash out everywhere.
You attach a filter with screws or tabs which hold it in place so it doesn’t tip over from any direction.
When installing cartridges, sponges, and media baskets in their designated place, the manufacturer’s instructions will help you.
You need to prime the filter before plugging it in. Initially, air surrounds the pump’s impellers, which are pushed out when water rushes into them.
To ensure that the HOB filter is in working order, fill it with water before switching it on. As soon as the water starts flowing through your filter -the impellers have started functioning.
Some models of HOB power filters have an auto-priming feature that allows you to place them into a water-filled aquarium without any difficulties.
There will be gurgling noises in the first few minutes as air is replaced with water around the impeller blades and then operating smoothly after this process completes.
HOB filters are an inexpensive and easy way to keep your tank clean. You can DIY them by adding sponges, pads, or whatever you find fit for your tank.
Vibration and noise may happen during the first hour after installation – nothing to worry about it!
Canister Filters
- Unbox the filter and check everything is in good condition.
- Rinse the filter media in freshwater thoroughly.
- Place cartridges inside the media trays.
- Arrange media trays inside the canister.
- Place the motorhead to its designated place (top or base).
- Keep the canister under the tank.
- Connect the hose and tubes (follow the manual).
- Remove trapped air from the canister by water filling.
- Prime the pump with water if needed.
- Turn on the filter.
In canister filters, the water is drawn up through a lift tube that sucks up all the dirty and contaminated water to enter its external chamber. There it passes through multiple kinds of filtering media before being made perfectly pure again.
When installing cartridges in canisters, you have to be mindful of the flow direction. Different brands have their own flow direction from bottom-to-top or top-to-bottom, back-to-front, and the opposite.
Each canister contains filter cartridges that have three primary functions:
- Initial mechanical filtration removes unwanted particles from the water, such as dirt and debris.
- There are chemical filters to remove odors and discoloration.
- Biological media provides housing for bacteria within your fish tanks, so they help eliminate ammonia and nitrites.
A water pump runs the canister filter, which is either attached to the cover or base. Alternatively, you might need an additional stand-alone water pump for this purpose.
Canisters can be equipped with a variety of filter media. These include cartridges, baskets, bags, and DIY chambers.
Canister filters are great for large tanks because they provide excellent circulation capacity.
Internal Air-Powered Filters
- Find the plastic strainer inside the filter and take out the bull’s eye.
- Place an air stone inside the strainer.
- Connect it to the bull’s eye directly or with a small piece of airline tubing.
- Snap the bulls-eye back on the strainer and put it back into the sponge.
- Connect the other end of the strainer to the filter’s weighted base.
- Place the lift tube over the airline tubing and clamp it.
- Submerge the filter into the aquarium water.
- Turn on the filter.
In these filters, water is pumped by an air pump and installed below the water level. These filters need to be hung using suction cups on the side of a filter.
As you take apart the air-powered filter, spread all of its parts out onto a clean table or floor. This will help ensure that nothing is missing from your aquarium’s new filtration system before putting it back together again!
In a power failure, you may notice water being pushed back into your air-powered aquarium filter. This is caused by the check valve failing to function correctly and can be prevented with proper installation of this device in accordance with manufacturer instructions.
Air-powered aquarium filters available in the market usually contain a few simple items inside the box, including the check valve, air pump, airline best lift tube, or air stone.
The prerequisites for installation are to first rinse and disinfect the filter because it might have worm eggs or microscopic algae stuck to it.
Internal Submersible Filters
- Rinse the filter media in freshwater thoroughly.
- Install the cartridges and media baskets in their designated places.
- Place the filter on the back/side wall of your tank with suction cups.
- Submerge the filter into the aquarium water.
- Turn on the filter.
An internal submersible filter is exactly the same as a HOB filter, except it’s submerged in water and not hung at the back of a fish tank.
The entire box, including its motor and cartridges, must be fully submerged underwater for these filters to work correctly.
Suction cups or clips secure the filter to an aquarium.
The pump pulls in air and sends it through a nozzle, which can be adjusted by valves included with the purchase.
These filters should be used on smaller tanks or fish bowls to keep parameters stable to avoid increased maintenance.
How To Replace Used Fish Tank Filter Cartridges?
In general, you have to follow the following steps to replace fish tank filter cartridges:
- Turn off all the power.
- Unscrew the box and loosen the cover of the filter box.
- Take out the used filter media from the tray.
- Place the new filter media into the cartridge slot.
- Install the filter box.
- Turn everything on.
How Often Should I Change My Aquarium Filter Cartridge?
How often to change a fish tank filter cartridge can vary depending on the bioloads of your aquarium. More specifically, how much waste and free-floating algae are in the water.
Most general recommendations are once per month. And you need to make sure you’re changing or cleaning the filter in the correct way.
Related posts:
- How to Clean Canister Filter [A Step-By-Step Procedure]
- How To Clean Aquarium Filter Sponge [3 Effective Ways]
- How To Change Aquarium Filter Without Losing Bacteria?
Can A New Filter Kill Fish?
Replacing the filter cartridge of your aquarium can be detrimental to fish. This is because it removes beneficial bacteria and makes the nitrogen cycle of the tank unstable.
Like sudden water changes, a filter cartridge replacement can alter the water chemistry, which can be fatal for your fish.
Is It Okay To Have Two Filters In A Fish Tank?
If your aquarium is large enough, it’s excellent to have multiple filters for the tank. However, in some cases, having several smaller ones can be advantageous over a single larger filter.
Can You Over Filter A Tank?
No, it is not really possible to over-filter an aquarium, but inadequate filtering is quite common! Filtering an aquarium is extremely important for maintaining a healthy fish tank.
To ensure that your water quality remains in good condition, aim to purchase a filter slightly larger than the requirement of your aquarium, as this will provide better filtration capabilities and a healthier environment overall.
How Do I Know If My Fish Tank Filter Cartridges Need To be Replaced?
I recommend checking if your filter is still working by observing bubbles from the top of your filter outlet. If there are no bubbles, it may not be properly functioning, or cartridges are blocked. Because water should be bubbling through these pipes, or else you need to replace this cartridge.
In addition, I suggest visually inspecting the condition of aquarium water and testing for quality using a device like an API Master Water Testing Kit.
Measure pH levels plus Ammonia, Nitrate, and General Hardness – if everything is normal, your filter is working correctly. Otherwise, think about filter maintenance (including cartridge replacement.)
Final Words
Aquariums have become popular home décor pieces in recent years due to their visual appeal and relaxing qualities of watching fish swim around the tank while sitting on one’s couch or bed!
As you can see, there are no alternatives to using a filter in your fish tank.
You must know the procedure to install a fish tank filter cartridge – it will benefit you from easy installation and maintenance to help maintain the health of your habitat.
So if you have any questions or would like more information on this topic, please leave a comment below!
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