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Canister Filter vs Power Filter (HOB Filter)

An aquarium can change the look of any place and also add positivity. The little fishes swimming around in glee brings a smile on everyone’s face. And, you can easily spend hours watching them in awe.

As a fish owner, if you think just buying an aquarium and introducing fishes ends your task, then you are wrong. You have to also think about the health of the fishes and plant lives within the tank.

For the purpose, one of the most important things you need is a tank filter. If you are wondering what a tank filter is and why you need one then continue reading to discover your answer.

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The Purpose of Tank Filters

The purpose of a tank filter is to eliminate decaying organic matter, excess food, and dangerous chemicals. It also helps remove fish wastes and free-floating particulate from the tank water.

The fishes keep excreting waste while they swim. If the waste keeps collecting then the toxins that the fishes are removing from their system will build up in the tank. Gradually, it will reach to such an amount that fishes will die.

Furthermore, decaying food, particulate, and other organic matter that floats in the water will make it look cloudy, if not controlled. To handle these problems you need a tank filter. It will make sure the water in your aquarium always stays healthy through mechanical, biological, and chemical filtration.

Filtration Methods

In Mechanical Filtration, particulate matter is eliminated from the aquarium water. To make this possible, the tank water is forced through a media that catches these little particles. To make sure the media works well you need to clean it on a regular basis.

In Biological Filtration, beneficial bacteria help break down nitrite and ammonia. It is then transformed into compound nitrate, which is far less toxic. For these helpful bacteria to develop, a good surface area like sand or rocks and oxygen-rich water is needed. Biological filtration is very important for all aquariums

In Chemical Filtration, chemical additives help eliminate dissolved wastes present in the tank water. Activated charcoal is most commonly used for chemical filtration.

So, filtration is important and thus you must invest in a tank filter. Among the various kinds of filters available, canister filters and power filters are becoming increasingly popular. We will share a canister filter vs power filter (Hob Filter) comparison. This will help you understand which will be a better choice for you. But before that, let us get to learn about both of them in detail.

What Is a Canister Filter?

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Canister filters are basically pretty powerful and large filtration units. Chances are, you will not come across a more efficient or stronger unit than a canister filter. You do get them in nano sizes as well.

Such filters work from outside an aquarium. Just the tubing that is used to draw in the water is inside, while the rest remains outside.

Setting up and maintaining canister filters require a bit of knowledge and thus experienced aquarists will find it easier to handle. These filters need hoses, routine cleanings, biological filtration, and can be a little pricey.


Canister filters will require some maintenance. The maintenance will usually depend on the model, brand, and the kind of media used.

Before cleaning, you need to take the filter apart. The media too needs to be cleaned and after that, you will have to replace the media.

Keeping in view the type of media you use some will require you to rinse it more often. As soon as you notice your filter is not working the right way, take it out and clean it well.

Chances of Water Loss

Canister filters are not near the top of the aquarium and return water with the help of a spray bar. This reduces both the current and evaporation. There is no need to worry about water splashing out when it is being directed back into the aquarium.

Chances of Loss of Fishes

As far as losing fishes is concerned, you do not have much to worry about if you have a canister filter. As the top of the aquarium has no opening your fishes will have no route to jump off. They will always stay inside happy and safe within the closed top of your beautiful fish tank.

Pros and Cons of Canister Filters


  • Great filtration power.
  • Ample space for housing media which ensures perfectly clean tank water.
  • Comparatively the strongest motors and pumps.
  • Since they are mostly placed outside, they save a lot of space inside the fish tank.


  • Can be quite expensive.
  • They need you to have at least a little knowledge to use and maintain it.

Check Price and Reviews on Amazon

Video: “PetSolutions: Cascade Canister Filters”

What is a Power Filter?

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Power filters (HOB Filter) are a great option for beginners. It is a good choice if you have a small fish tank and do not want to spend too much on filtration.

These filters are simple and are also known as hang on back (HOB) filters. They are external and you need to hang them over the back of your tank’s rim. They do save you a lot of space. This is in fact what both canister and power filter share in common about which we shall also discover in the canister filter vs power filter (Hob Filter) comparison.

Power filters can easily be installed. Just place them over your aquarium’s rim, turn it on and it is ready to be used.


It is quite easy to maintain a power filter. All you have to do is remove the carbon or other kinds of media that your model and brand support and replace it. You do not have to remove your whole filter, not unless something goes wrong with the water sucking tube.

You also always do not need to replace the media. While changing the water if you feel the carbon filter does not need to be replaced then just wash it and place it back again. If it needs to be changed then simply swap it out.

Chances of Water Loss

Power filters lose quite a lot of water when you clean and return the water back to your aquarium. As the water is exposed when it is on its way back, it encourages evaporation. Thus, you lose lots of water. However, you need not really worry much about this. As there will be an increase in the surface area there will be an improvement in the level of dissolved gases. This means the oxygen level for your fishes will be closer to what you get in the air.

Chances of Loss of Fishes

You require quite a big opening in your aquarium to fit in a power filter. This can create a route for your fishes to escape if the water level is way too high. This applies to the crustaceans or amphibians present in your aquarium as well.

Pros and Cons of Power Filters (HOB Filter)


  • Power filters are pretty small and thus do not take much space.
  • Very easy to install and use.
  • Maintaining them is also very easy.
  • They are quite inexpensive.


  • They cannot handle too much water and are not a good choice for high volume fish tank
  • Though they are cheaper, they might not be very durable.

Check Price and Reviews on Amazon

Video: “How to Set Up and Install a Marineland Penguin Filter”

Canister Filter Vs Power Filter (HOB Filter)

Let us now draw a comparison between these two and learn how they are different and what do they share in common.

What do they share in common?

  • Both of them are external filters.
  • Both of them support mechanical, biological, and chemical filtration.
  • Both offer very good filtration, making the tank water clean and healthy.

How are they different?

Power filter is easy to set up and use and thus a great choice for beginners. On the other hand, setting up and using a canister filter needs a bit of knowledge. This will be more suitable for experienced aquarists.

Power filters are generally easy to maintain. It needs minimal and frequent upkeep. In contrast, you will need to invest more time and effort to maintain a canister filter.

Though both of these filters are external their placement is different. Power filters hang on the back of a tank whereas a canister filter usually is placed below a tank in a tank cabinet.

There is an opening which serves as a route for fishes to escape in case of a power filter. On the other hand, canister filters have a close top and there is no way fishes can jump off and escape.

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Now that we have gone through the canister filter vs power filter (HOB Filter) comparison it will be fair to conclude that both of them are good in their own ways. Both of them have a good set of features and their own share of pros and cons.

You need to consider the size of your aquarium, and how much time and money you want to invest. Also, think about the efforts you are ready to put in and it will be quite easy for you to decide on one. No matter which one you choose you can be sure your aquarium will enjoy a good filtration. The water within will always stay clean and healthy and your fishes will be safe and happy.

Aaron Boyd
Aaron Boyd

Hello, I’m Aaron Boyd, the proud owner and author behind Aqua Movement. I hope my article was able to answer your questions. If you want to learn more about me, click the home icon above.

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