From garden ponds filled with Koi Carp to the humble goldfish bowl (although goldfish are far happier living in a larger tank) – the UK is a nation of fish lovers.
There are an remarkable five million indoor fish tanks in the UK alone, according to the Pet Food Manufacturers’ Association (PFMA).
That’s about 10 per cent of British households – making fish the third most popular pet after dogs and cats.
It’s a fascinating hobby, particularly for youngsters, and there are few more relaxing activities than watching fish slowly swim around their home.
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There’s plenty of choice when it comes to adding fish to (well prepared and correctly set up) home aquariums, with pet shops offering a bewildering range of finned friends that will happily live in the corner of your living room.
The first decision to make is whether you are going to pick a freshwater or saltwater tank - saltwater is a little more demanding - before choosing your fish breeds.
It’s important to ensure that you get the right fish for your particular aquarium or your pets will not be happy and healthy.
If space (and money) is no object then there are some incredible huge tropical fish you can opt to put in your enormous tank.
Here are 12 of the biggest - and most colourful - tropical fish for freshwater aquariums.
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1. Oscar
Oscars can reach 12–14 inches in length and are quite remarkable animals - they are intelligent and interactive fish, able to recognise their owners and display unique personalities. These fishy monsters are best kept in large tanks with strong filtration due to their delightfully messy feeding habits. | Canva/Getty Images
2. Silver Arowana
Growing up to three feet, the mighty Silver Arowanas are powerful surface-dwelling predators. Known for their metallic sheen and jumping ability, they require massive tanks, secure lids, and are best kept solo or with strong tankmates - these fish are proper carnivores. Although they need a large aquarium, they'll only occupy the top couple of feet. | Canva/Getty Images
3. Banded Leporinus
The Banded Leporinus is a stunningly-patterned fish that can grow up to a foot in length. They enjoy living in small schools so if you are looking for a pack of fish to dart around your enormous tank then these are a good choice. They just love to jump, so make sure that lid is good and secure. | Canva/Getty Images
4. Pacu
With those bitey-looking wee faces the Pacu is often confused with the notorious Pirahha, but they couldn't be more different when it comes to diet, being entirely peaceful carnivores. They may be chilled but they are not small - growing to over two feet. That heft and their active swimming style means they need plenty of room in a tank. | Canva/Getty Images