5 Best External Filters of 2021

Guide to External Filters

If you’re thinking about getting an external filter for your aquarium, then you are in luck. We have researched and found the 5 best models of 2021 that will work with any size tank setup. External filters are a simple way to clean up the water in your tank without having to constantly change it yourself, saving you time and money!

What is an External Filter?

An external filter is a system that sits outside of the tank and connects to it using an inlet pipe and outlet pipe. It relies on gravity for its function, which keeps the inside surfaces cleaner because water doesn’t flow over them when it’s being cleaned.

External filters can be used either as a replacement or add-on to your current filtration system. They’re great if you have an irregularly shaped tank or one with difficult corners where debris could accumulate without regular cleanings by hands, such as under rocks or other decorations. The filter also provides additional aeration through a built-in air pump – this creates more dissolved oxygen in the aquarium and improves gas exchange between organisms living there!

What is the purpose of an External Filter?

External filters are designed to be placed in the cabinet underneath an aquarium and connect to the main tank using an inlet pipe and outlet pipe. The filter is also used as a secondary filtration system for tanks that are too small or irregularly shaped to fit a traditional internal filter. In these situations, external filters provide mechanical, chemical, and biological cleaning of water without adversely affecting your fish’s natural behavior patterns because it doesn’t require them to live inside the filter like they would with an interior design!

External filters are larger and more powerful than internal filters, and as a result, they’re much more effective at removing debris. Some models even come with UV sterilizing lamps to help kill any bacteria or algae living in the water!

Best External Filters – FAQ

What is an external filter?

As the name suggests, external filters sit outside the tank in the cabinet below. Water is sucked out of the tank and enters the filter, where it is cleaned and then pumped back up to the tank. External filters have much more media inside them than internal filters, so they tend not to need cleaning quite as often.

Which external filter is best?

Best Aquarium Canister Filters Reviewed
Fluval External 07 Canister Filter Series (Top Pick)
Fluval External 206 Canister Filter Series.
EHEIM Classic External Canister Filter.
SunSun Pro Canister Filter Kit.
Fluval FX6 Canister Filter.
Hydor Professional External Canister Filter.

How does an external filter work?

External filters are at the high end of filtration – they draw the water out of the aquarium into an external box or canister, where the water is pushed (by a water pump) through a series of different filters, and then back into the tank.

Are external filters better?

External filters are larger and more powerful than most internal filters and can hold a lot more media, offering better cleaning and supporting more fish. The superior power of external filters makes them suitable for large aquaria; heavily stocked aquaria like African cichlid tanks; and large fish.

Are sponge filters better?

Generally, sponge filters are good for most fish tanks.
However, there are instances where they really shine.
Sponge filters are excellent due to their gentle flow.
This allows for set-ups for fry, betta, and shrimp tanks that thrive in low-flow filtration.

Can you over filter a fish tank?

You can’t really over-filter an aquarium, but it’s fairly easy to under-filter one.
This rating system works well, for the most part, however, heavily populated aquariums or those with large predatory fish or fish that generate large amounts of waste should be fitted with oversized or multiple filters.

Is a sump better than a canister filter?

Canister filters usually have a lower maintenance need than power filters and sumps because the water is being forced through the media as opposed to flowing over or around the media. Most of these filters also return water to the tank via a spray bar. This reduces evaporation and current.4 days ago

What are the different types of aquarium filters?

Canister filters.
Diatom filters.
Trickle filters.
Algae filters.
Baffle filters.
Fluidized bed filter.
Airlift filters.
Undergravel filters.

Should filters be underwater?

Internal filters must be completely submerged in the water to work correctly.
The air bubbles create much-needed movement in the water that allows it to filter the liquid throughout the entire tank.
The filter can be affixed with suction cups to the tank walls, or placed on the ground of the tank.

What is the best fish filter?

Best Overall: MarineLand BIO-Wheel Power Filter.

Best for Freshwater: Penn Plax Cascade 700 Canister Filters.

Best for Saltwater: AQUATIC LIFE RO Buddie Reverse Osmosis Systems.

Best for 20-Gallon: Tetra Whisper IQ Power Filter for Aquariums.

Best for 75-Gallon: Seachem Tidal 75 Large Aquarium Fish Tank Filter.

What is the best filter for a 20-gallon tank?

What is the best filter for a 5-gallon tank?

Best nano filters for aquariums up to 5 gallons & Betta fish
Aqua Clear 20 power fish tank filter.

Azoo Mignon 60 Power Filter.

Penn-Plax Small World Aquarium Filter (SWF1)
Marina S10 Power Filter.

Aquatop Classic Aqua Flow Sponge Filter CAF-10.

Aqueon Quietflow E Internal Power Filter.

Finnex Pure-5 Power Aquarium Filter.

Do sponge filters actually work?

Sponge filters work well as a pre-filter on the inlet of a canister filter.
The sponge filters out a good deal of the larger particulate matter, which keeps the canister from clogging.
It is far easier to clean or replace the sponge pre-filter often, rather than tearing apart the canister filter.

How long does a sponge filter last?

There are two particular answers to this. One says you need to clean your sponge filter every two weeks, and the other says you can clean it after several weeks. Both these answers are correct and for very different reasons.

Are sponge filters noisy?

There are two places where sponge filters make noise: First, bubbles breaking the surface of the water. Nothing you can do about this other than turn up the TV louder.

Can a fish tank have 2 filters?

If your aquarium is large enough, it is completely fine to have multiple filters for your fish tank. There are even some instances where having multiple filters can be more beneficial than one large filter.

Can I use a small filter on a big tank?

As long as you keep the flow of the water under control, it can be a good idea to have multiple smaller filters in your fish tank rather than one large one. If one of the filters stops working, you will still have some filtration in your tank until you get a replacement.

What is the best biological filter media?

The Best biofilter media
Biohome Ultimate Filter Media.

Seachem Matrix Bio Media.

Fluval Biomax Bio Rings.

Marineland Bio-Filter Balls.

EHEIM Substrat Pro Biological Filter Media.

What is the best media for a canister filter?

For advanced chemical filtration, Marineland activated carbon is one of the best filter media for canister filters around.
Long-lasting, heat-activated, and specially sized (small granules) proves more efficient than other forms of carbon.

What order do you put filter media in?

Media Order