For fishkeeping purposes, tropical fish can be defined as those which require a constant water temperature of between 72°F and 86°F, depending on species (most of the species available in the hobby thrive best at around 77°F).
Below we take a quick look at the types of tropical fish
that are available to the Aquarist.
Catfish are found all over the world. Most species are nocturnal, coming out of their refuges at night to feed. One group of catfish specialise in algae-eating which makes them popular cleaner fish in aquariums.
Cichlids are a very large group of fish, comprising thousands of species spanning the globe. They are popular in aquaria as they have very interesting, readily observable behaviour patterns, especially when breeding.
Characins are the ever popular tetras and their relatives, mostly small schooling fish which are considered an essential inclusion to most community aquaria. Beware though, this group includes the piranhas!
Cyprinids, or carp-like fishes, include barbs, loaches and danios, and are plentiful in Southeast Asia, occupying niches in which tetras and catfish are found in South America.
Anabantoids, also known as Labyrinth Fish, comprise Gouramis, Bettas (fighting fish), and Climbing Perch. They possess an organ which allows them to breathe atmospheric air, enabling them to survive in oxygen-poor environments.
Killifish include some of the most stunning tropical fish to be found. There are two types - one breeds by burying its eggs in the substrate and the other by attaching eggs to plant leaves. The former types are short lived, usually surviving no more than 6 months in the average aquarium. The latter can live several years, and make beautiful and interesting additions to a community set-up.
Oddballs cover all fish species which don't fit into the above categories but have some feature which makes them interesting to fishkeepers. This could be appearance, behaviour, rarity or anything else which appeals to the aquarist's taste for the unusual.
Discus are known as the King of Aquarium Fish. Their notoriety as the most demanding, impressive and expensive tropical fish has ensured their continuing popularity amongst enthusiasts. They have been selectively bred to the extreme, providing the aquarium hobby with several hundred different colour forms.
Livebearers include the most ubiquitous of tropical aquarium species, the platies, swordtails, guppies and mollies. Many different colours and patterns have been produced by selective breeding. These are most people's first tropical fish, and their popularity shows no sign of declining as they are colourful, peaceful, hardy, small and incredibly easy to breed.