Gourami Fish Care Tips:

Tank Size: The minimum tank size suitable for most Gouramis is 20 gallons for a pair.
Tank Setup: Gouramis enjoy planted tanks. Ensure you heavily plant the tank with decent amount of space for the Gouramis to swim around.
Water Temperature: Optimum water temperature for most Gouramis is between 74 to 79 F (24 to 26 C).
Water Filtration: In wild Gouramis are found in ditches, canals, ponds, swamps etc. A filter with a moderate flow is suitable for the Gourami tank.
Water pH Level: The suitable pH for most types of Gourami is between 6.0 to 8.0.
Food: Gouramis can practically eat anything. Fish food like flakes, freeze dried foods and live foods small enough to fit its mouth should be given to Gouramis.
Number of Fish: Depending on the type of Gourami, at least 4 to 6 Gouramis are recommended to shoal together in the tank.
Tankmates: Different Gourami species, Killifish, Danios, White Cloud Minnows, Neon Tetras can be housed along with Gouramis.

References:

Caring for and Breeding Gouramis

Gourami


https://www.thespruce.com/gourami-care-and-breeding-1378303

Dwarf Gourami Care Guide


http://www.encyclopedia.com/plants-and-animals/animals/vertebrate-zoology/gourami
http://www.fish-species.org.uk/aquarium-fish/25-dwarf-gourami.htm

Dwarf Gourami Care: Tank Mates, Size, Temperature & Disease


http://www.allaquariuminfo.com/2011/11/gourami-information-types-care-and.html
https://www.thespruce.com/blue-gourami-1381023