• External filters can be kept outside of the tank with one pipe going into the tank, and one pipe going out of the tank. This looks much better than internal filters that need to be placed inside the tank- this can make the tank look a bit cluttered/take up room in the tank.
  • External filters can be placed out of sight- they can easily be placed into the cabinet underneath the tank, if space permits.
  • External filters have a much larger media capacity- meaning that filtration is greatly improved and is much more efficient due to a much larger surface area for beneficial bacteria to grow on.
  • They can also increase the aquarium water capacity- as the filter can hold a few litres.
  • You have the ability to place a wider variety of filter media into the external to suit your needs. They can also be placed in such an order that is preferential to you.
  • External filters are generally easier to maintain, as they can be cleaned and changes to filter media can be made, without even going into the tank.
  • External filters are capable of achieving much higher flow rates than internal filters- therefore making them effective in filtering large aquariums.
  • Attachments can be used on the outlets of the external filter, controlling how the flow enters the tank. 
For more information see our blog post on how you can choose the correct filter.