A fairly typical 60l (2’) unheated set-up.
Too small for Goldfish, but there is still a variety of species that are suitable.
An unheated tank is a popular choice for a first aquarium.
Sometimes driven by childhood memories of that first “easy to keep” fairground goldfish in a bowl; sometimes due to the practicality of available sockets or a desire to keep tank furniture to a minimum.
Although they may seem the obvious choice, Goldfish aren’t necessarily the best choice and they are certainly not the only choice for an indoor unheated tank.
Contrary to many people’s memories of how easy it was to keep a Goldfish as a child, they are in fact large, messy fish requiring a good sized tank and over-sized filtration if they are to thrive into old age.
Remember that the average indoor unheated tank is not truly coldwater.
It is, in fact, temperate or sub-tropical.
If located in a draft-free position in a warm room, many unheated tanks in UK homes will rarely drop below 18°c and can run as warm as 24-25°c during the Summer months (maybe even more).
Therefore, there is quite a surprising range of species far better suited to that small / medium unheated tank than Goldfish.
Below is a brief overview of just some of the species that are suitable for unheated tanks.
Jordanella floridae American Flag Fish
* photographs show male (left) and female (right)
Geographical Distribution : North America
Family : Cyprinodontidae
Temperament : Potential for fin-nipping with long-finned species
Adult Size : 6cm
Preferred temperature range : 16-26°c
Puntius gelius Golden Barb
Geographical Distribution : Southern Asia
Family : Cyprinidae
Temperament : Peaceful / community
Adult Size : 5cm
Preferred temperature range : 18-25°c
Puntius semifasciolatus Chinese Barb / Gold Barb
Other variants include Schubert’s Barb and Green Barb
Geographical Distribution : South-eastern Asia
Family : Cyprinidae
Temperament : Peaceful / community
Adult Size : 7cm
Preferred temperature range : 18-25°c
Puntius conchonius Rosy Barb
long finned variant also available
Geographical Distribution : Southern Asia
Family : Cyprinidae
Temperament : Peaceful / community. Potential for fin-nipping if kept in small numbers
Adult Size : up to 14cm, often smaller
Preferred temperature range : 18-25°c
Puntius arulius Arulius Barb
Geographical Distribution : Southern Asia
Family : Cyprinidae
Temperament : Peaceful / community. Potential for fin-nipping if kept in small numbers
Adult Size : 10-12cm
Preferred temperature range : 19-25°c
Tanichthys albonubes White Cloud Mountain Minnow
Geographical Distribution : China
Family : Cyprinidae
Temperament : Peaceful / community
Adult Size : 4cm
Preferred temperature range : 16-22°c
Danio rerio Zebra Danio
variants include Long-finned, Golden and Leopard Danios
Geographical Distribution : Southern Asia
Family : Cyprinidae
Temperament : Peaceful / community
Adult Size : 6cm
Preferred temperature range : 18-25°c
Danio albolineatus Pearl Danio
Geographical Distribution : South-eastern Asia
Family : Cyprinidae
Temperament : Peaceful / community
Adult Size : 6cm
Preferred temperature range : 18-25°c
Danio choprai Glowlight Danio
Geographical Distribution : Myanmar (Burma)
Family : Cyprinidae
Temperament : Peaceful / community
Adult Size : 3cm
Preferred temperature range : 19-25°c
Macropodus opercularis Paradise Fish
Geographical Distribution : South-eastern Asia
Family : Belontiidae
Temperament : Territorial. Do not mix with males of the same species or other anabantoids
Adult Size : Up to 10cm, often smaller
Preferred temperature range : 16-24°c
