Black Tetra, Black Widow, Petticoat Fish, Blackamoor Gymnocorymbus ternetzi
ternetzi, Tetragonopterus ternetzi
PD: This fish is somewhat oval-shape.
Young are more attractive than adults. The main
body color is dark gray to black while the fins are black.
Older fishes’ colors fade and their fins and
body color become smoky gray.
Two black bands extend vertically; one just behind the gill cover and the other in its
SIZE: To 2.5" (6.4 cm)
HAB: South America; in shaded, calm areas with plants thickets in small brooks in rainforest
tributaries, of the Rio Negro, Rio Paraguay, and Rio Parana.
TANK: 20" (50 cm) or 10 gallons (38 l).
The tank should be well-planted and
arranged in dark colors.
Use a cover of floating plants to diffuse the lighting.
Leave an open area for free-swimming.
WATER: pH 5.8-8.2 (6.8), 4-28 dH (8), 72-82°F (22-28°C)
SB: A peaceful, schooling fish that is an excellent community fish.
Occasionally large, adult males can
become aggressive towards smaller fish, but this is not usually a problem in a well-planted tank.
Keep in a school of at least five individuals.
SC: Tetras, Corydoras,
Apistogramma, Discus, Angelfish, Livebearers, Gouramis, Rasboras,
FOOD: Live; insect larvae, crustaceans, aquatic insects; flake.
SEX: Males are smaller and slimmer. Females have rounded dorsal fin and a rounded body
cavity when seen against the light.
B: This fish is easiest to breed in a breeding tank with marbles as a substrate or a mesh
netting for the eggs to fall out of reach of the cannibalistic parents.
Use warm water (84-86°F) to initiate
After courting procedure of the male swimming around females with fins spread, many tiny transparent
eggs that fall to the bottom.
Parents must be removed or eggs will be eaten.
The eggs hatch in 24-28 hours and the
fry are free-swimming after 3 to 5 days after.
Start feeding with small live and crushed flake foods.
Breeding the Black Tetra is not difficult.
R: The are variants of this fish who have longer, more elaborate fins. These are slightly
harder to care for because these fins are often nipped at.
A gold variety is also a product of selective
This fish matures in about a year.
A hardy fish ideal for a beginner's community tank.
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