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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9. Common Plecostomus
They may be small in the pet shop but don't be fooled - the Common Plecostomus (or Pleco) can easily reach 18-24 inches in length. These algae eaters are perfect for keeping your tank clear of the green stuff and, as long as they have a few hiding spots, they can thrive in a large community tank. | Canva/Getty Images
10. Jack Dempsey
Originally from Central American countries like Mexico and Honduras, the Jack Dempsey Fish is named after a famous 1920s boxer thanks to its fearsome face and aggressive nature. Best kept alone in a tank, it's also important to provide them with somewhere to hide away - all 10 inches of them. | Canva/Getty Images
11. Tinfoil Barb
Reaching 14 inches, Tinfoil Barbs are fast, peaceful, and social bars of scaley silver. Best kept in schools, they need a large tank and strong currents. They’re not aggressive but may bully smaller fish out of their food. | Canva/Getty Images
12. Bichir
Primitive and eel-like, growing up to 24 inches, the Bichir is another fish as likely to give you nightmares as fill you with wonder. We think they are amazing though, with their feathery fins and armor-like scales. They are bottom dwellers but have the ability to breathe air so will regalarly pop up to the surface for a breather - meaning a tight lid is essential. | Canva/Getty Images