Through selective breeding, the pink convict cichlid was bred due to a genetically mutated color caused by an autosomal recessively inherited gene. This phenotype lacks the dark black stripes that their wild counterparts display.

The convict cichlid's 8 to 9 vertical black stripes have a zebra-like pattern and are reminiscent of the earlier striped prison uniforms. All of this contributes to their well-known name, as does their scientific name Nigrofasciatus, which literally means "black-striped".

One of the most popular African cichlids in the aquarium hobby is the lemon jake peacock cichlid, which is likely due to their display of various colorations and patterns that are uncommon in most other species and has a calmer disposition than most other cichlids.

One of the most popular African cichlids in the aquarium hobby is the eureka red peacock, which is likely due to their display of various colorations and patterns that are uncommon in most other species and has a calmer disposition than most other cichlids.

Siamese fighting fish are among the first known species of fish in the aquarium industry, having been domesticated since the earliest accounts in Thailand in the 14th century. They are a popular fish among aquarium enthusiasts due to variations in color and morphology that emerged as a result of domestication, producing a vast array of distinct colors, patterns, and fins.

Since most species of fish inhabit the lower and middle levels of the aquarium, aquarists looking for a distinctively shaped fish to incorporate into a community tank with other fish of similar size and temperament will like the black-winged hatchetfish.

Empire gudgeon fish are known for their adaptability, active swimming behavior and impressive color displays during courtship and competition for females. While females and juveniles are usually brown, olive or golden, mature males can develop brilliant orange-red coloration with contrasting black and pale blue fin markings.

The empire gudgeon is one of around 11 species in the most widely distributed genus found in Australia, Hypseleotris. Their present family, the Gobiiformes, was previously a suborder of the Perciformes, which once contained 2,211 species but has since been divided into seven families.