Keeping Fish

How to choose the best aquarium filter

How to Choose The Best Aquarium Filter for Your Fish Tank

Choosing the best aquarium filter for your fish tank requires a little bit of thinking, making the wrong choice could cause problems for your fish and setup. In this article, we take a look at aquarium filters and how you should determine the best filter for your fish tank setup.

Some images and products shown in this article are affiliate links, we may earn a small commission, we hope you find the information useful.

Aquarium Size

Before investing in a filter it is important to establish the size of your fish tank, this is important especially if you are upgrading to a larger tank.

Many beginners would have probably purchased an aquarium kit to start off, this would have come with an aquarium filter, it is not best practice simply to use the same filter when setting up a larger fish tank.

Aquarium filters are required to filter the water in your fish tank and to achieve this it’s important that the flow rate is sufficient enough to keep the water clear and provide the correct filtration.

Always check the water volume of your fish tank because this will help you to purchase the correct flow rate required.

Aquarium filters will in most cases have their flow rate and water volume size printed on the box when new so ensure this information doesn’t fall short of your filtration requirements.

Types of Aquarium Filters

There are many different types of filters for fish tanks that can be used to filter your water, they all achieve the same purpose so it does not matter which type you choose as a filtration system for your fish tank, but ensure it is large enough to cope with the volume of water in your tank. Let’s take a look at the different types of aquarium filters best for keeping fish.

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Hang on Back Aquarium Filter

The hang-on-back filter is a popular choice for fish tanks up to approximately 100 ltrs in water volume, they simply hang onto the back of the fish tank. The hang on the back filter will work fine on larger fish tanks especially if you don’t have live plants or a large amount of fish in the tank.

allpondsolutions 500 L/H Aquarium Hang On Back Fish Tank Filter with 5w UV...
  • 500L/H External Hang-On Filters for aquariums up to 115L with Built-in 5w UV Steriliser Suitable for...
  • Waterfall outlets provides more oxygen to fish tank water
  • Providing mechanical and chemical filtering to ensure proper oxygenation for a clear water and a...

Last update on 2024-05-26 / Affiliate links / Images from Amazon Product Advertising API

Canister Aquarium Filter

The canister filter is a good choice for larger fish tanks they provide a really good flow rate capability and are really good if you keep live plants in your aquarium, also the filter is not located inside the tank it is an external filter that does not impose on the aesthetics of the aquarium.

allpondsolutions EF2 Aquarium External Fish Tank Water Filter for Coldwater,...
  • Suitable for fresh and salt water aquarium fish tanks
  • Easy priming unit - simple setup
  • Large filtration volume!

Last update on 2024-05-26 / Affiliate links / Images from Amazon Product Advertising API

Sponge Filter

The aquarium sponge filter is becoming more popular with fish keepers who keep smaller fish they provide both mechanical and biological filtration, this type of filter is not in my opinion best suited if you keep larger fish in your aquarium. The sponge filter does make a great secondary filter if you keep shrimp, betta fish, turtles, or other small fish, plus they are great for breeder tanks.

hygger Aquarium Double Sponge Filter Super Biochemical Filter Sponges for...
  • Sponge filters provide both mechanical and biological filtration -- Provides the ideal location for...

Last update on 2024-05-26 / Affiliate links / Images from Amazon Product Advertising API

Internal Filter

The standard internal filter is the most common type of aquarium filter, this type of filter is easy to set up, and it simply sticks to the glass with suction cups on the inside of the fish tank. The internal aquarium filters are available in different sizes and have various flow rates. The only disadvantage of using an internal filter is that they do take up valuable space inside the tank especially if the fish tank is not a large one.

Marina Internal Filter i160 for aquariums up to 160 L,Black,Large
  • The marina i160 enhances aquarium water quality and is ideal for goldfish or tropical tanks.
  • Overall it is quiet, compact and powerful.
  • Bottom positioned motor for quiet operation and the waterfall spout for continuous oxygenation
  • Bio screen provides large surface area for growth of friendly bacteria

Last update on 2024-05-26 / Affiliate links / Images from Amazon Product Advertising API

Aquarium Filter Cleaning

Aquarium filters require regular maintenance to ensure they always provide the best filtration for your tank.

This cleaning process should only be done when you see that the water is starting to look dirty with particles floating in your water, this shows that the filter is not performing as it should.

The filter itself builds up healthy bacteria for your tank so the cleaning process should not be done in your kitchen sink as it will remove the quality bacteria that you want to keep.

We recommend that any cleaning process to your water filter should be done when you do a partial water change, clean the filter in the bucket of dirty water you have removed from the tank. Cleaning your aquarium filter in your fish tank water will minimize the risk of killing the good bacteria in your filter plus there will be no chlorine from tap water contaminating the filter.


In conclusion, choosing the best aquarium filter for your fish tank is a personal choice as all types will filtrate the water in an aquarium.

When choosing an aquarium filter ensure that the filtration and flow rate of the filter is large enough for the volume of water you need to filter in your aquarium.

Internal aquarium filters take up space in the aquarium reducing the amount of room your fish have to swim.

External filters such as the hang-on aquarium filter and the canister type filter do not take up space in the fish tank and are a cleaner method of filtration as the external components of the filter will not get dirty with algae, fish waste, or plant matter.

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