Moonlight Gourami

A Unique Labyrinth Fish

Moonlight gourami (Trichopodus microlepis), also known as the mo
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The common name Moonlight Gourami describes this peaceful labyrinth fish quite well. Its body is silver colored with a slightly greenish hue that is not unlike the soft glow of moonlight. The concave slope of the head in the Moonlight Gourami distinguishes it from other Gourami species.

Characteristics

Scientific NameTrichogaster microlepis
SynonymsOsphromenus microlepis,Trichogaster microlepis, Trichopus parvipinnis, Deschauenseeia chryseus
Common NamesMoonlight Gourami, Moonbeam Gourami
FamilyBelontiidae
OriginThailand, Cambodia
Adult Size6 inches (15 cm)
SocialPeaceful, suitable for a community tank
Lifespan4 years
Tank LevelTop, Mid dweller
Minimum Tank Size20 gallon
DietOmnivore, eats most foods
Breeding

Egglayer–bubble nest

CareIntermediate
pH6.0–7.0
Hardness2–25 dGH
Temperature79–86 degrees Fahrenheit / 26–30 degrees Celsius

Origin and Distribution

The Moonlight Gourami originates in the tropical areas of Vietnam, Thailand, and Cambodia. It prefers still or slowly moving waters with plenty of vegetation such as ponds, bogs, swamps, and lakes. They are also found in the floodplains of the Mekong River. As it has been bred in captivity in various parts of the world, it has escaped from breeders and become an invasive species in Singapore and Columbia. This species is also farmed for food in Southeast Asia. Most Moonlight Gouramis intended for the aquarium market are bred in captivity.

Colorings and Markings

The Moonlight Gourami is long and flat; its head has a concave curve. Its ventral fins boast long filaments which are sensitive to touch; males' pelvic fins are red while females' pelvic fins are yellow or colorless.  It has small, silvery scales which, as it matures, develop a pretty greenish iridescence. Its eyes are red or orange.

About Labyrinth Fish

Like all labyrinth fish, Trichogaster microlepis has a special organ that allows it to breathe air directly. Because if this labyrinth organ, it is not unusual to see it go to the surface and gulp air. The ability to breathe air allows them to survive in very low oxygen situations.

In fact, if it remains moist it can actually survive out of water for up to several hours.

Tankmates

Moonlight Gouramis can be kept in pairs or groups in a community tank, so long as there are hiding places for the least aggressive in the group which are sometimes bullied. Other tankmates can include other labyrinth fish and larger species such as Redtail Botia, Corydoras, and Angelfish. Avoid fin-nipping species such as Clown Barbs, as the Moonlight Gourami has long filaments on its fins which are very tempting.

Moonlight Gourami Habitat and Care

Sturdy vegetation such as Java Fern and Vallisneria are excellent choices. Although it makes a beautiful addition to a community tank don't be surprised if it hides regularly. Even under ideal conditions, this is a fish that tends to be timid. It should be kept only with non-aggressive fish.

Although undemanding about water conditions, it does best in soft acidic water. Because it is so tolerant of less than perfect water, it is a good beginner fish. However, the water should be changed regularly to keep to maintain good health.

Moonlight Gourami Diet

The Moonlight Gourami will eat flake, frozen, and live foods. Serving a good variety of live and flake foods will help ensure optimum health.

If you have a community tank with other large fish, make sure they aren't scaring the Moonlight Gourami away from the food. This is a timid fish who will not fight for its dinner, even if very hungry.

Sexual Differences

Females are wider than males and have more rounded anal and dorsal fins;  males can be identified by the orange to red coloration of the pelvic fins, as well as the long dorsal fins that end in a point. In females, the pelvic fins are colorless to yellow, and dorsal fins are shorter and rounder. ​During spawning, males' ventral fins turn from orange to red. 

Breeding the Moonlight Gourami

The Moonlight Gourami is an egg layer that builds a bubble nest as most Labyrinth fish do. Breeding of this fish is both easy and interesting. They should be provided a separate breeding tank, as other fish consider eggs and small babies (fry) a tasty snack.

The ideal breeding tank has very soft water that has been reduced to a depth of about six inches. pH should be slightly acidic, and the temperature should be raised to at least 80 degrees over a period of several days to trigger spawning. Use dark gravel and provide plenty of floating plants for building the bubble nest. Feeding the breeding pair live foods before attempting the breed them will increase your chances of success.

The male begins the spawning process by carefully preparing a bubble nest. He then begins to court the female under it. This courtship dance is a fascinating display that should not be missed. Spawning culminates in the male wrapping himself around the female. While in this embrace the male turns the female onto her back, which triggers her to release eggs. Up to 2000 eggs may be laid during the spawning, which the male fertilizes as they float up to the nest. In the safety of the bubble nest, the eggs incubate for two to three days before hatching.

Once the eggs hatch, the fry must be fed very fine foods several times daily. Most losses of fry are due to lack of adequate food or low water temperature. Live foods such as daphnia, artemia, and rotifers, are ideal. However very finely chopped lettuce, banana skins, and finely ground flake food can be used to feed the young (and are usually easier to find). Keep the water temp in the low to mid 80's while the fry (tiny juveniles) are growing.

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