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.
And while the size of tank is only limited by your budget and available space in your home, there are plenty of beautiful fish that will thrive in a smaller tank.
So, here are 12 of the best species of fish for aquarists (the posh name for people who maintain aquariums) who only have room for a small tank.
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5. Least Killifish
Used to living in stagnent, muddy water in their native North America, a clean five litre tank is positively luxurious for the Least Killifish. There's no problem with space either - they are the seventh smallest breed of fish in the world. | Canva/Getty Images
6. Scarlet Badi
Another tiny nano fish, female Scarlet Badis barely reaches a single centimetre in length, with males only a little bigger, meaning a smaller tank will not be a problem. They can be fairly sensitive to changes in acidity, so regular ph tests are a must. | Canva/Getty Images
7. Ember Tetra
If you are looking for a decent-sized school of fish to dart around your small tank then the tiny Ember Tetra is worth consideration. Smaller than other tretras they are easy to look after and provide great colour for your aquarium. | Canva/Getty Images
8. Zebra Danio
Also known as the Zebra Fish. the Zebra Danio is another schooling fish that doesn't need an enormous tank. Around six will happily live in smaller aquarium. These little fish from South Asia will eat pretty much anything so that's one less thing to worry about. | Canva/Getty Images