Peacock Gudgeons (Tateurndina ocellicauda) are native to Papau New Guinea, where they inhabit slow-moving rvers or ponds. At about two inches, they are not very large, but their bright and vibrant colors are what make them stand out. They are schooling fish, and though the males may compete for territory or mates, they are generally very peaceful.
A peacock gudgeon in the aquarium
The larger, more colorful males can also be distinguished by a hump on their foreheads that is absent in females. Males tend to guard small caves in which to attract females and to guard the eggs--and this is possible to replicate in captivity. In the aquarium, they are best kept in small groups of 6 or more, with females outnumbering the males. Moderate light and a dark substrate will bring out their colors, while caves and live plants will make them feel more comfortable in their environment.
In the wild, they eat smaller crustaceans or insects; in the tank brine shrimp is perfect staple. It is often difficult to get them to accept prepared foods, as they are fairly picky eaters. Good tankmates would include other peaceful, smaller fish such as corydoras, platys, raspboras, etc.
Peacock Gudgeons in an aquarium