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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1. Chili Rasbora
The Chili Rasbora is so small it's categorised as a nano fish - not even reaching a couple of centimetres in length. They are used to living in shallow water in the swamps of South West Borneo, Indonesia, so a small tank will be perfect for them to live. | Canva/Getty Images
2. Endler’s Livebearer
A couple of the pretty Endler’s Livebearer fish can be kept in a five litre tank. They come in a range of colours, from the silver females to the bright different hues of the male. Originally from Venezuela, they were once thought to be extict. If you go for this breed it's best to keep the ratio of males to females at 1:1 to endure a happy environment. | Canva/Getty Images
3. Sparkling Gourami
More than living up to its name is the half inch-long Sparkling Gourami, with a rainbow of colours glinting from its glitterball body. They are fine in a modestly-sized tank, although make sure you have some live vegetation for them to enjoy zipping between. | Canva/Getty Images
4. Guppy
The beautiful Guppy is one of the most low maintenance tropical fish out there - and will happily live in a small aquarium amidst other species. Also known as the Millionfish or Rainbow fish - which have large multi-coloured tails and originally come from northeast South America. In common with some other common aquarium fish, they live-birth their young, rather than laying eggs. Many first time fish owners have been delighted to wake up one morning to find tiny Guppy babies have arrived overnight. | Canva/Getty Images