Tropical fish

Tropical fish are generally those fish found in aquatic tropical environments around the world, including both freshwater and salt water species. Fishkeepers often keep tropical fish in freshwater and saltwater aquariums.

Tropical fish is a term commonly used to refer to fish that are kept in heated aquariums. Freshwater tropical fish are more commonly kept than Saltwater tropical fish due to the common availability of fresh water sources, such as tap water, whereas Saltwater is not commonly available and has to be recreated by using freshwater with sea salt additions. Salt water has to be monitored to maintain the correct salinity because of the effects of evaporation. Freshwater tropical aquariums can be maintained by simply topping up with fresh water. Tropical fish are popular choices for aquariums due to their often bright coloration, which typically derives from both pigmented cells and iridescent cells. Tropical fish may include wild-caught specimens, individuals born in captivity including lines selectively bred for special physical features, such as long fins, or particular colorations, such as albino. Some fish may be hybrids of more than one species.

Most fish that are sold as tropical fish are freshwater species. Most species available are generally bred from fish farms in the far east and Florida where tropical temperatures make the commercial production more viable. Mass production of tropical fish from farms has led to many inexpensive fish available to aquarists. Tropical freshwater fish are the most popular group of fish because of the low price and ease of keeping in aquaria. for Some species are difficult to breed in captivity and so are still sourced from the wild. These species are generally more expensive. Among the bred in captivity species most expensive species are arowanas and flowerhorns. Some male flowerhorns are sterile due to many cross breeding.

Marine fish that are sold as tropical fish are generally sourced from the wild, usually from the coral reefs around the world. This is because only a few species of marine fish have been successfully bred in captivity with any regularity. The price of marine fish coupled with the difficulty in keeping them alive in aquaria makes them less of a popular choice for aquarists to keep. However, because of the more vivid colours, patterns and behaviour of marine fish compared to freshwater fish they are still reasonably popular. The advances in filtration technology and increase in available knowledge on how to maintain marine fish as well as the increasing number of aquarium bred species is seeing a gradual rise in their popularity.

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