Large Fish Tanks
4ft to 7ft aquariums, up to 700 litres – made to order in the size you need.
Big, stable and built to last. Our large fish tanks are made from 10 mm float glass, come with a no-leak warranty of up to 3 years and are delivered across mainland UK – as a bare tank or as a complete set with cabinet and cover.
Large aquariums for serious fishkeepers
We design and build large fish tanks for homes, offices and fish rooms – from 4ft tanks to 6 x 2 x 2 ft and 7 x 2 x 2 ft aquariums. Choose a ready size from our shop or order a fish tank made to your exact dimensions.
- 10–12 mm glass – float or Optiwhite, clear or black silicone
- Up to 3-year no-leak warranty on our aquariums
- Custom sizes and shapes – including L-shaped tanks
- Matching cabinets and covers available for every size
Why choose a large fish tank?
A large fish tank is not just a bigger version of a small one. More water means more stable conditions: temperature changes more slowly, waste is diluted in a bigger volume and the whole system is far more forgiving if something goes wrong. That is why experienced fishkeepers often say that a large aquarium is actually easier to look after than a small one. It also gives you room for bigger and more active fish, proper shoals, large cichlids, marine fish or a long, natural aquascape that simply would not fit in a standard 3ft tank.
At Aquaexpert we sell and manufacture aquariums, cabinets and complete aquarium sets, and most of what we build is customised and made to order. Our range of large fish tanks starts at around 4ft and goes up to 7ft long tanks of about 700 litres, with custom shapes such as L-shaped aquariums built to your own drawing.
Popular large fish tank sizes
When customers ask us for a “big tank”, they usually mean one of these sizes:
- 4ft (120 cm) tanks – a great first step into large aquariums. Our 120 x 50 x 50 cm 270L fish tank suits freshwater, tropical and marine set-ups.
- 5ft (150 cm) tanks – around 490–500 litres in a 150 x 60 x 60 cm footprint, ideal for living rooms that need a real centrepiece.
- 6ft (183 cm) tanks – the classic 6 x 2 x 2 ft size. Our 650L 72″ x 24″ x 24″ aquarium is one of the most popular large fish tanks we make.
- 7ft (213 cm) tanks – about 700 litres of water in our 84″ x 24″ x 24″ 7 x 2 x 2 ft tank, for serious fishkeepers and large species.
If none of these fits your room, we can build a custom aquarium made to order or an L-shape fish tank based on your measurements.
Glass thickness and build quality
The bigger the aquarium, the more pressure the glass has to hold. Our large fish tanks are made from 10 mm float glass, and some premium models use 12 mm glass with specially reinforced joints, where every layer of bonding silicone is protected by a glass strip. You can choose clear or black silicone, a rimless look or bracing, and on selected sets even Optiwhite (low-iron) glass for crystal-clear viewing. Most of our large aquariums come with a warranty of no leaks for up to 3 years.
Bare tank or complete set?
Many hobbyists already have a stand, a sump or their own filtration, so they only need the glass. That is why we sell large fish tanks as bare tanks – usually with glass lids – and also as complete sets. If you are starting from scratch, a set is the safer choice: the cabinet, the cover and the tank are designed together, so the dimensions match perfectly. Take a look at our aquarium with cabinet sets, or compare sizes and prices on our fish tank with cabinet guide.
Planning space and weight
Before you order a large fish tank, think about where it will stand. A 6ft tank holds roughly 600–650 litres of water, and the empty glass alone weighs around 100–115 kg. Add substrate, rocks and the cabinet, and the total weight can easily go above 800 kg. Place the aquarium on a strong, level floor, ideally close to a load-bearing wall, and always use a dedicated aquarium cabinet or a metal frame stand rather than ordinary furniture. Leave space above the tank for maintenance and lighting, and plan access to a power socket and to water for changes.
Freshwater, tropical or marine
Our large tanks are built for all water types. Freshwater and tropical keepers love the long 6ft and 7ft footprints for planted aquascapes and big shoals, while reef keepers choose the same sizes for marine aquariums with a sump in the cabinet. If you plan a heavily planted tank, add a CO2 cylinder and a reliable heater and equipment from our shop.
Made to order – what to expect
Because most of our aquariums are built to order, each product page shows its own lead time, typically between 3 and 8 weeks for large tanks. We deliver across mainland UK. Large aquariums are shipped on a pallet with kerbside delivery, so please check the order carefully on arrival and report any damage straight away. Deliveries take place Monday to Friday between 07:00 and 17:00.
Need a size that is not listed?
Send us your measurements, the type of fish you want to keep and a photo of the space. We will suggest the right glass thickness, cabinet and cover, and prepare a quote for your custom large fish tank. Contact us or browse all aquariums and sets in our shop.
