These filter canisters do not have a pump, so they are connected into the water exit line on your existing canister filter and pumped through this booster unit. They can be used for both freshwater and saltwater aquariums.
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USB Filter Wall-Mounted Waterfall Filter Fish Tank External Filter For Small Aquarium Remove Oil
Aliexpress UK
Superfish Eco-Flow 120. The SuperFish Eco-Flow 120 is supplied complete with hoses and all necessary accessories. Compact and economical external filter for aquariums up to 120 liters. This filter is simple and easy to use and maintain.
eBay
Transparent Aquarium Tank with Clip On Lamp External filter Desktop Small Fish Tank Aquarium for
Aliexpress UK
This is an all-in-one external canister filter for any freshwater or marine aquarium. Flow rate is 120 GPH and will work with 20 to 40 gallon aquariums. Flow rate: 120 GPH. Great for freshwater planted aquariums.
eBay
SUNSUN XBL Series Aquarium Filter Wall Mounted Filter Barrel External Fish Tank Small Silent Hang on
Aliexpress UK
Aquarium Fish Tank Filter Hang on Back - HOB Filter 2 Sizes 20 Litres upto 200 Litres. This is a German engineered and designed powerful yet quiet filter. Retractable Water Inlet. Made of high-quality ABS material, non-toxic and odorless, it will not harm your fish.
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UUIDEAR Factory Supply Aquarium Filter Aquarium Accessories Stainless Steel External Canister Filter
Aliexpress UK
Hang of the back filter (HOB) are a perfect aquarium filter for those who want to save space int he aquarium. Compact hang-on aquarium filter. USB plug (adaptor needed). inlet protection foam to prevent fry/shrimplets being sucked into the filter.
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EHEIM Fish Tank Aquarium Small External Wall-mounted Filter Compact Barrel Automatic Start Filter
Aliexpress UK
Energy Saving, High Power: tank hanging filter adopts scientific structure, which makes the pump very powerful and energy saving. Suitable for freshwater and seawater fish tanks. Easy to Install: Wall mounted small fish tank hanging filter, quick and easy to install, convenient to use.
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220V SOBO fish tank filter wall-mounted filter barrel three-in-one external filter small grass tank
Aliexpress UK
BENEFICIAL OXYGENATION - Unique waterfall flow design, can create beneficial bacteria in your nano tank. The key to the success of the aquarium is having the perfect filter. This aquarium hang on filter has a powerful & whisper-quiet filter system, which is both safe and durable.
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SUNSUN HW 404B 505B 507B 702A 702B 704B Aquarium External Filter Fish Tank Canister Optional 9w UV
Aliexpress UK
Activated Carbon - Granulated Carbon Filter Media For use in aquariums, fish tanks, ponds, internal filters, external filters and sumps. We sell small stone granulated carbon filter media which has a larger surface area that traditional pelleted products and therefore greater effectiveness. What is Activated Carbon? Activated Carbon is a form of carbon that has been produced with extremely high micro porosity. Carbon is good at binding to most elements and molecules which means that when fluids are passed through it or over it, contaminates or pollutants contained within the water will be caught by the carbon reducing improving the purity of the water. One gram of Activated Carbon has a surface area of between 1500m2/g to 3000m2/g.
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Fish Tank External Filter Box Acrylic Filter Dry and Wet Separation 4 in 1 Small Silent External
Aliexpress UK