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.
One think you should be aware of is that while many of the most popular fish, such as the Neon Tetra, need a heated tank, others are more than happy to chill in a cold water (or more accurately speaking a room temperature) aquarium - although you’ll still need a filtration system to keep them in tiptop fishy-shape.
Here are 12 amazing species of fish perfect to populate an unheated aquarium.
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1. Paradise Fish
Found across East Asia, the Paradise Fish is one of the most exotic-looking fish that can thrive un an unheated aquarium. Surprisingly hardy, the males can be aggressive, so be careful what fishy friends you choose to introduce into their tank. | Canva/Getty Images
2. Goldfish
Undoubtedly the world's most popular aquarium fish, the Goldfish comes in a whole array of sizes, shapes and colours (not only gold, but also combinations of white, yellow, orange, red, brown, and black). Don't be tempted to pop one on a tiny bowl, these fish may be hardy but still need plenty of space and filtration to thrive. Originally from China, these are the perfect cold water fish for beginners. | Canva/Getty Images
3. Hillstream Loach
Looking for something more unusual for your cold water aquarium? The Hillstream Loach could be your fish! Unusual and eye-catching, they resemble miniature stingrays. These algae-eaters love fast-moving, oxygen-rich water and do well in cool temperatures with plenty of rocks and hiding spaces. Originally from South, Southeast and East Asia, there are around 202 subtly-different species of Hillstream Loach, although your local petshop will probably only have a couple. | Canva/Getty Images
4. Rosy Barb
The Rosy Barb is a fish that is equally at home in a tropical or cold water aquarium. Colorful and lively, they and are relatively easy to care for and are a schooling fish - so best buy a few. Originally from southern Asia, they’re active swimmers needing space and some plant cover. | Canva/Getty Images