The Fluval 20 Litre Betta Aquarium Kit has been designed specifically around the needs of Betta splendens. Rather than taking a conventional small aquarium and simply putting a Betta name on it, Fluval has developed the filtration, heating, lighting and cover to create the warm, gently flowing environment these fish prefer.
With a maximum capacity of 22.7 litres and approximately 18.9 litres of swimming volume, it’s an excellent size for keeping a single Betta while still being compact enough for smaller spaces.
Fluval 20 Litre Betta Aquarium with Gentle Filtration
Strong currents can be troublesome for Bettas, particularly the ornamental varieties with large, flowing fins.
The Fluval 20 Litre Betta Aquarium Kit tackles this with a specially designed intake that draws water through multiple slots spread across a larger area. This reduces the strength of the current entering the filtration system and helps protect delicate fins.
Water then passes through a dedicated diffusion chamber before returning to the aquarium. This spreads the return flow across wider outlets, creating the gentler water movement Bettas prefer.
Multi-Stage Betta Filtration
Despite the gentle flow, Fluval hasn’t compromised on filtration.
The rear filtration compartment uses mechanical, chemical and biological media to help remove debris and dissolved contaminants while providing plenty of surface area for beneficial bacteria.
Included are a foam filter block, Poly-Carbon insert, BIOMAX and diffusion chamber pad, so the filtration system is ready to set up straight from the box.
The pump is adjustable between approximately 100 and 350 LPH, allowing the circulation to be reduced if required.
Fluval 20 Litre Betta Aquarium with 25W Heater
Bettas are tropical fish and shouldn’t be kept long-term in an unheated aquarium in a typical UK home.
Fluval therefore includes a 25W pre-set heater, neatly concealed within the rear filtration compartment. It is designed to maintain the aquarium at approximately 26°C, right in the preferred temperature range for Betta splendens.
This is a particularly useful feature compared with basic Betta tanks where a suitable heater has to be purchased and installed separately.
Soft-Glow LED Lighting
A built-in 5W LED light provides a softer style of illumination rather than flooding the aquarium with excessively bright light.
It produces approximately 420 lumens with a colour temperature of 7500–8000K, providing attractive illumination for the aquarium while maintaining the more subdued environment Bettas generally appreciate.
Adding live plants, wood and other areas of cover can make the aquarium even more comfortable while creating a much more natural-looking display.
Integrated Water Change System
One of the cleverest features of the Fluval 20 Litre Betta Aquarium Kit is its integrated water-change valve.
This allows old aquarium water to be drained directly from the filtration system without needing to disturb the fish or manoeuvre a siphon around a relatively small aquarium. Once the required amount has been removed, simply refill with correctly treated and temperature-matched freshwater.
It’s a small detail, but one that makes regular maintenance considerably easier.
A Cover Designed for Bettas
The supplied aquarium cover performs more than one job.
It helps reduce evaporation and prevents a Betta from jumping from the aquarium, while also helping maintain a layer of warm, humid air above the water. This is useful because Bettas are labyrinth fish and regularly breathe atmospheric air from the surface.
A removable section also provides convenient access for feeding.
What’s Included?
22.7L glass aquarium
Aquarium cover
Soft-glow LED lighting
LED power supply
25W pre-set heater
Adjustable circulation pump
Foam filter block
Poly-Carbon filter insert
BIOMAX biological media
Betta diffusion chamber pad
Why We Like the Fluval 20 Litre Betta Aquarium Kit
There are an awful lot of tiny tanks marketed for Bettas, and many of them aren’t particularly well suited to keeping one properly.
This is different.
Fluval has actually considered the things that matter: gentle circulation, proper filtration, tropical heating, a secure cover and easy maintenance. The rear filtration chamber also keeps most of the equipment out of sight, leaving the main aquarium looking considerably neater.
For somebody wanting a smart dedicated home for a single Betta without having to select every piece of equipment separately, it’s a very well thought-out little aquarium.
Fluval 20 Litre Betta Aquarium Specifications
Maximum volume: 22.7 litres / 6 US gallons Swimming volume: Approx. 18.9 litres / 5 US gallons Dimensions: 30 × 28 × 43cm (L × W × H) Filtration: Multi-stage rear filtration Pump: Adjustable, approximately 100–350 LPH Heater: 25W pre-set heater Temperature: Approx. 26°C Lighting: 5W soft-glow LED Light output: 420 lumens Colour temperature: 7500–8000K LEDs: 14
If you have any questions about this Fluval 20 Litre Betta Aquarium Kit and whether it’s suitable for your aquarium, please contact us and a member of our friendly store team will be more than happy to answer all of your questions.
