Australian Rainbowfish | Melanotaenia fluviatilis

Rainbowfish / Melanotaeniinae / Australian Rainbowfish

Profile: Australian Rainbowfish
Melanotaenia fluviatilis Synonyms: Aristeus fluviatilis, Melanotaenia splendida fluviatilis, Nematocentris fluviatilis
Physical description: An elongated species have lateral compression.   This species lacks the tall body height characteristic of its genus.  The head is small while the eye is large.   There are two dorsal fins and the caudal fin is slightly forked.  The anal fin has a long base and is pointed at the end.   The back is yellow-brown while the flanks are silver-brown with a silver to green iridescence.  A broad blue band runs from the snout to the caudal fin.   This may often be fain in some places.  The rear half of the body is marked with several orange-red lateral stripes.   The fins, except for the caudal fin, are yellowish with orange-red markings and a dark edge.   The caudal fin does not have a dark border.  The rear part of the iris of the eye is orange-red as is a marking on the gill cover.   Females are less colorful, lacking the orange-red stripes.
Size/Length: To 4" (10 cm)
Similar species: Melanotaenia maccullochi, M. nigrans, M. splendida
Habitat: Australia; New South Wales and Queensland
S: middle
Aquarium: A tank measuring 32" (81 cm) with a volume of 30 gallons (114 L) is suggested.   The tank should be well planted along the back and edges and have open swimming areas.   A fine gravel substrate is preferred and the lighting can be bright.  Use good aeration.
Water chemistry: pH 7-8 (7.2), 5-12 dH (8), 72-79°F (22-26°C)
Social behavior: A peaceful, schooling fish recommended for a community tank.   Should be kept in groups.  
Suggested companions: Other Rainbowfish, livebearers, tetras that can tolerate harder, more alkaline water.
FOOD: Live; insect larvae, crustaceans, worms, insects; flakes
SEX: Males are more colorful
Breeding techniques: Use a well-planted, roomy tank with a temperature from 75-81°F (24-27°C).   Pairing is preceded by vigorous chasing.  Spawning usually takes place at dawn and continues for several days.   The first day results in 100-200 eggs, with decreasing numbers each day.  The dark eggs are attached to plants by fine threads.   These hatch after 7-8 days.   The parents may eat the eggs, especially if not fed adequately.   The young can first be fed paramecia and later Artemia nauplii.  The fry grow slowly until reaching 0.4" (1 cm), when growth rate increases.
Breeding potential: 6.  Breeding is moderately easy.
Remarks: The the validity of this species is in question; some feel that it is a sub-species or a cross.
Difficulty of care: 4.  A hardy fish suggested for a community tank.   Preform frequent partial water changes.