Internal Filters

Internal aquarium filters provide the biological and mechanical filtration that is necessary to give aquatic life a healthy environment and crystal clear water. To ensure optimal filtration, it’s important to match your internal filter to your tank size. Internal fish tank filters and under gravel filters are suitable for small to medium tanks. For larger aquariums, an external filter will be required. 

We have a huge range of internal filters for aquariums available to buy online. If you are unable to find the product that you're looking for, or just need some advice about choosing an internal fish tank filter, don't hesitate to call our team of aquatic experts on 01566 771878.

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Sicce Micron Internal Filter - 300 L/HSicce Micron Internal Filter - 300 L/H
Sicce Micron Internal Filter - 300 L/H
Micron, internal filter for aquariums up to 75 litres of capacity. The Micron Internal Filter features a floating rotor system and anti-wear device, allowing you to adjust the filtering, dependent on the aquarium water volume. Features suction cups for tank fitting. To ensure perfectly clean water for at least 30 days, the filter uses an active carbon filter with zeolite. Flow Rate: 300 LPH Power...
£13.99 inc VAT

Aqua One Maxi Aquarium Internal Filters
Aqua One Maxi Aquarium Internal Filters
The Maxi range of Internal filters offer an effective biological and mechanical filtration solution for the smaller aquarium. Proven reliability and silent running Completely submersible sealed motor, economical to run Provides mechanical and biological filtration with high quality foam as media Built in venturi nozzle Complete with suction cups for fixing to side of aquarium
from £15.99 inc VAT
Oase BioCompact 25
Oase BioCompact 25
The OASE BioCompact 25 is a compact biological and mechanical filter with integral pump, for use in smaller marine or fresh water aquariums up to 25 litres (5.5 Gallons). The BioCompact can be vertically or horizontally mounted, making this ideal for use in paludariums also. The fully submersible 240L/Hour pump is concealed in the top section of the filter and is both quite and energy efficient,...
£15.99 inc VAT

Tetra InPlus Internal Aquarium Filters
Tetra InPlus Internal Aquarium Filters
Tetra IN plus Internal Filters Sizes Available - IN300, IN400, IN600, IN800, IN1000 Easy-to-use internal filters for keeping aquarium water healthy Filter start button makes starting filter easy Snap valve shuts off water flow for no-mess access to media Robust design Comes complete with media and pipework Easy maintenance - no need to remove the entire filter, as all components can be quickly...
from £26.99 inc VAT
Eheim Pick-Up FilterEheim Pick-Up Filter
Eheim Pick-Up Filter
The filter is fixed in the tank with suction holders. The special feature of the pick up concept is that the pump unit remains in the tank when the filter canister is taken out together with the filter sponge. The motor body at the bottom sucks in the water and conveys it through the filter sponge. Afterwards the cleaned water is returned to the tank through the adjustable outflow nozzle. EHEIM pick...
from £16.99 inc VAT

Eheim Mini Up Micro Aquarium FilterEheim Mini Up Micro Aquarium Filter
Eheim Mini Up Micro Aquarium Filter
Eheim Mini Up Micro Aquarium Filter It’s small, gives excellent performance and is simple to fix to the tank with suction cups. The filter sucks the water in through vents, carries it through the filter sponge and directs it further up, cleaned, back into the tank. You can also connect an outlet hose in order to adjust the outflow direction. Unobtrusive, slim design Front water intake Connection...
£19.99 inc VAT
Fluval Underwater FilterFluval Underwater Filter
Fluval Underwater Filter
The filter is simple to attach in the tank with suction cups. The filter canister together with its cartridge can be removed from above, while the pump unit remains in the tank. This is a very practical solution for cleaning or changing the filter cartridge. The pump sucks in the water from below and carries it through the filter cartridge to the top. The filtered water is directed back into the tank...
from £23.99 inc VAT

Oase BioPlus Internal Corner Aquarium FilterOase BioPlus Internal Corner Aquarium Filter
Oase BioPlus Internal Corner Aquarium Filter
Oase BioPlus Internal Aquarium Filters are designed to be compact and to fit discreetly and unobtrusively into the corner of your aquarium. Everything you need is included and the unit is easily mounted to your aquarium via the attached suction cups. Available in 3 sizes to suit aquariums up to 200 litres they offer the efficiency, reliability and quality that Oase have already become well known for...
from £24.99 inc VAT
Sicce Shark ADV Internal Aquarium FilterSicce Shark ADV Internal Aquarium Filter
Sicce Shark ADV Internal Aquarium Filter
Shark ADV is equipped with the patented magnetic connecting system (MCS) and an air flow adjustment with 4 settings, to compensate low water movement in the tank with grater aeration. Features a fast releasing wall coupling & wide angle swivel positioning. Encompasses a modular filtering system with interchangeable active-carbon, micro-porous sponge cartridges. Magnetic connecting system with...
from £31.99 inc VAT

Eheim Aquaball Internal FilterEheim Aquaball Internal Filter
Eheim Aquaball Internal Filter
EHEIM aquaball – the variable modular system with a spherical head. The outflow direction can be adjusted as required. EHEIM aquaball offers you an internal filter concept with all-round benefits The ball is the trick. The round pump head sits in a ball joint. This enables adjustment of the outflow direction as required. The flow rate is set by the output regulator. And the power-diffusor...
from £29.99 inc VAT
Eheim Biopower Internal FilterEheim Biopower Internal Filter
Eheim Biopower Internal Filter
EHEIM biopower – the first internal filter with external filter technology and multi-layer filtration. It combines the flexibility of the EHEIM aquaball with the effectiveness of a compact external filter. With EHEIM biopower you have a high performance internal filter that has never before existed. It has got its all-round rotatable pumphead, its modular construction and further features from...
from £39.99 inc VAT