Best Aquarium Filters & Pumps — Up to 81 Litre (2026)
1 aquarium filters & pumps matching capacity “Up to 81 Litre”, hand-picked from UK Amazon listings.
Not sure which one to pick? Read our How to Care for & Maintain Your Aquarium Filters & Pumps guide.
Maintaining a healthy environment for your smaller aquarium fish or invertebrates is crucial, and the right filtration system makes all the difference. This selection of aquarium filters & pumps caters specifically to tanks up to 81 litres, providing powerful yet quiet operation suitable for a range of setups. These units are designed to effectively remove waste products like ammonia and nitrite, which are highly toxic to fish, ensuring optimal water quality. Investing in one of these pumps will contribute significantly to the long-term wellbeing of your aquatic companions.
#1 Pick
Interpet Internal Aquarium Fish Tank PF2 Power Filter, Cleans Water, for Coldwater & Tropical Aquariums Up to 81 Litre, Black/Blue- Up to 81 Litre
£24.15
Pros
- Next size up from the popular PF1, rated for tanks up to 81 litres
- Built-in venturi aerates the water while it filters
- Simple rocker switch and suction-cup mounting for quick setup
Cons
- Cartridge replacements are an ongoing running cost
FAQ
What kind of fish can I keep with an 81 litre filter?+
You'll have more flexibility with smaller community fish like Neon Tetras, Guppies, Corydoras catfish, and small Rasboras. Larger goldfish or cichlids are generally not suitable for this size tank due to their increased waste production.
How often should I clean the filter?+
The frequency of cleaning depends on stocking levels and water quality. Generally, you'll want to partially clean your filter media every 2-4 weeks, or more frequently if you notice a build-up of debris or a drop in water parameters.
What type of filter media do I need?+
A combination of mechanical, biological, and chemical filtration is recommended. Mechanical media removes particulate matter, biological media hosts beneficial bacteria that convert harmful ammonia into nitrite, and chemical media can absorb impurities like nitrates.
Are these pumps quiet?+
Most models in this range are designed for low noise operation, though individual performance varies slightly. Check the manufacturer’s specifications or customer reviews for details on decibel levels before purchasing.
How do I connect the pump to the aquarium?+
Typically, these pumps have a flexible hose that connects directly to the outlet of your tank. Ensure you use appropriate silicone sealant to create a watertight connection and prevent leaks.
What power source does this filter use?+
Most filters in this category are powered by AC mains electricity via an adapter. Always ensure the voltage matches your local supply before plugging it in and consider using a surge protector for added safety.
How do I choose the right flow rate?+
For an 81 litre tank, a flow rate of around 20-30 times the tank volume per hour is generally recommended. This ensures adequate oxygenation and waste removal; however, check manufacturer specifications for optimal values.
Can I use these filters with planted aquariums?+
Yes, you can! These pumps are suitable for planted tanks, but consider adding root tabs to your substrate for additional nutrient support, and ensure the pump doesn’t disturb plant roots excessively.
What maintenance is required beyond cleaning the filter?+
Regular water changes (approximately 25% weekly) are essential for maintaining water quality. Monitor water parameters using a test kit to track ammonia, nitrite, and nitrate levels and adjust your routine accordingly.
Are these filters suitable for beginners?+
These filters are well-suited for beginner aquarists due to their ease of use and reliable performance. However, it’s still important to research proper aquarium care practices and understand basic water chemistry principles before setting up your tank.