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Nanochromis Transvestitus

Nanochromis transvestitus

Tiny river cichlid (5 cm). Famous for its extreme 'inverted' sexual dimorphism: the female is ablaze with stripes and a glowing red belly, while the male remains gray and faded. Very fragile, demands soft waters and very low pH.

Family
Cichlidae
Origin
Africa (Fiume Congo)
Origin
Extra-Amazon South AmericaAfrica and Madagascar
Tank use
Used in 0 tanks

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Species challenges
Temperature

24 °C - 27 °C

pH

5 - 6.5

Water type

Freshwater

Tank level

Bottom

Adult size

6 cm

Description

Geographic Origin and Biotope: Exclusive to Lake Mai-Ndombe (formerly Lake Leopold) in the Democratic Republic of Congo. It is an area of very pure stagnant and extremely acidic (pH 4.0) blackwaters, rich in vegetation and floating forests.

Taxonomy and Morphology: Travesti Cichlid (Nanochromis transvestitus). Discovered by Stewart and Roberts. The name "transvestitus" derives from the fact (unique or almost so in fish) that the female displays spectacular colors, while the male is insignificant (generally the opposite happens in Nature).

Social Behavior: Shy and fearful among the woods, very tied to the sandy bottom. Females are extremely aggressive and "brazen" during courtship, to the point of physically terrifying or exhausting a male not ready to mate.

Coloration and Sexual Dimorphism: Gorgeous females: they possess a swollen cherry-red/purple belly, intense red nuances on almost all fins, and anal/caudal fins marked by dazzling black and white streaks and spots. The male is faded gray-brown with vague iridescence (very visually disappointing).

Care and observations

Aquarium Setup: Strictly dedicated nano-tank (60 cm / 24 inches). Fine sand mandatory for digging. Dens under rocks (like volcanic) or roots in abundance. Minimal lighting filtered by floating plants, peat and dry leaves to saturate the water with tannins.

Diet and Feeding: Sifting micropredator. Needs exclusively frozen or live food (Daphnia, Brine Shrimp, Bloodworms). Very reluctant to accept dry food, which in any case must be specific for bottom fish and highly digestible.

Water Quality: Fish for True Experts (The Chemical Nightmare). It is incredibly delicate. Requires pH below 6.0, non-existent hardness (GH 0-2) and constant chemical filtration. Zero nitrates. Most transvestitus die from water stress in the amateur's tank.

Compatibility and Tankmates: Never in community aquariums. Keep them alone (Species tank) in a pair, or associated (in 100 cm / 40 inches tanks) with non-competitive African blackwater microfish that stay on the surface. Warning: the female can literally kill the male if not tolerated.

Aquarium Reproduction: Very difficult. The female digs under a root and attracts the male (if the water chemistry is not equal to that of a tea infusion, they will never lay). The larvae need live infusoria, the pH must remain rigidly acidic (4.5-5.5) so that fungi do not arise.

Risks and Diseases: Killings and Starvation. Besides the extreme bacterial fragility at neutral pH, the female is a ruthless tyrant. If the male refuses to mate or she is too insistent in a tank without inaccessible hiding places, the male will die in a few days from the stress of constant beatings.

Fish profile

Tank level
Bottom
Adult size
6 cm
GH
1 dGH - 5 dGH
KH
n/a
TDS
n/a
Conductivity
n/a

Image gallery

Licensed images linked to the species or, when marked, to the closest representative taxon.