Gouramis are a group of fish in the families Osphronemidae, Helostomatidae and Anabantidae. They have a labyrinth organ that acts sort of like a lung, which allows them to breathe air at the surface. In nature this adaptation enables them to live in shallow, stagnant, oxygen-poor water. Some gouramis are mouthbrooders, and some make bubble nests at the surface to incubate their eggs until they hatch. Males are usually larger and have brighter colors and longer fins. Several species have been selectively bred for different colors and fancier fins.
Gouramis are found throughout eastern and southern Asia, from Pakistan through Thailand, Vietnam, the Malaysian Archipelago, China and as far north and east as Korea and Japan. They live in slow moving rivers, swamps, marshes, canals, wetlands and temporary pools.
Many gouramis are found in soft, acidic water in the wild, however the majority of aquarium species sold today are raised commercially in water that has a higher pH and alkalinity than their native environments and so they are very adaptable. pH should be between 6.8 and 7.8, alkalinity between 3° and 8° dkH (50 ppm to 140 ppm), and water temperature should remain between 75° and 80° F.
A 30 gallon aquarium or larger is recommended for most species. Kissing gouramis get to be quite large and will need a 55 gallon tank or larger when full size. Dwarf gouramis can be kept in tanks as small as 10 gallons. Most gouramis are surface oriented, so having tall plants or ones that float at the top help make them feel at home. They will be less stressed and show their best colors in a well decorated aquarium. Keep a secure lid on the aquarium to prevent them from jumping out.
Male gouramis have a tendency to be aggressive towards each other, so they should typically be kept individually. Female gouramis usually tolerate each other well. Mixing different species or color varieties of gouramis should only be done in larger, well decorated tanks. Remember that blue, three spot, opaline, gold and lavender gouramis are all the same fish – they’ve just been bred for different colors! Gouramis are slow moving and are best kept with similar sized fish that are not fin nippers or too active. Larger tetras, livebearers other than fancy guppies, peaceful barbs, most danios and angelfish can all be good choices.