In focus - external aquarium filters
The ultimate goal when keeping an aquarium is that it's clean, looks good and the fish are healthy. Probably the most important piece of equipment in your set up to achieve this is your filter, and in our opinion the best types of filters are external.
External filters are just that - filters which sit outside of your aquarium, draw in dirty water from your tank through an inlet pipe, pump it through lots of types of media and pump the cleaned water back via a spray bar or outlet nozzle. These filters work on the same principles as internal filters but on a much larger scale.
Instead of having a couple of sponges to do your biological and mechanical filtration, external filters have larger capacities to hold more media to keep large or heavily stocked aquariums visibly and chemically clean. You're going from a unit that holds a few sponges to in effect a 'bucketful' of different types of media in individual compartments. You can also tailor the types of media in your filter depending on your set up. Some fish like soft water so you can add a softening pillow to one basket. If you have large messy fish you can add more mechanical media. Got nitrite problems? Then you can add more biological media. They are incredibly versatile to suit almost any problem. Being that much larger also means less maintenance as they don't need cleaning as frequently, a massive bonus for all you busy fishkeepers out there!
Another great advantage is that the main unit sits outside the aquarium so you don't lose swimming space and your equipment is hidden. Having an external filter also allows you to add other pieces of equipment onto a system using the pumping power of the filter. UV sterilisers, in-line heaters and surface skimmers can all be fitted to run in-line with the filter for optimum water quality.
External filters come in all shapes and sizes to suit any set up and budget. Smaller units filter aquariums of 20 litres up to our larger units which can filter tanks of up to 600 litres.