Blackline Tail Tetra (Moenkhausia costae) – Tank Bred

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Looking for a fish that glides through your aquarium like a silver arrow with attitude? The Blackline Tail Tetra (Moenkhausia costae) is a sleek, fast-moving schooling fish with a bold, jet-black stripe running from mid-body through the tail—like a racing stripe on a sports car. This underrated South American native is tank-bred and full of energy, giving your community tank that extra spark of contrast and movement.

Perfect for aquascapes that need motion without chaos, these tetras bring a calm, controlled energy to midwater zones and look especially stunning under soft lighting.

What We Love About This Fish:

• Clean, Bold Markings: The crisp black tail stripe pops against its metallic body
• Peaceful Yet Lively: Active swimmers that won’t bother other tank mates
• Great Group Dynamics: Schooling behavior adds coordination and movement
• Perfect Contrast Fish: A neutral-toned swimmer that makes vibrant tankmates shine

Natural Habitat:

Native to the shaded tributaries and forest streams of South America, where they cruise through leaf-littered waters with plenty of submerged roots and driftwood.

Aquascaping Ideas:

• Plants: Use bright green plants like Vallisneria, Dwarf Sagittaria, or Limnophila to make their silver sheen pop
• Hardscape: Driftwood archways and smooth stones to mimic streambeds
• Botanicals: Indian Almond Leaves and Catappa Bark add tannins and bring out their natural behavior

Diet & Feeding Tips:

Feed a mix of micro pellets and quality flakes daily. Boost their coloration and vitality with occasional servings of frozen daphnia, baby brine shrimp, or bloodworms. They’re eager eaters and quick to learn feeding routines.

Tank Mates & Compatibility:

Excellent with peaceful fish like pencilfish, ember tetras, dwarf cory cats, and hatchetfish. Avoid fin-nippers or anything large enough to view them as a snack.

Shrimp Safe?

Mostly! Safe with adult Neocaridina and Caridina shrimp. Like most tetras, they may snack on baby shrimp if they stumble across them.

Breeding Notes:

Breeding is possible in a dimly lit, soft-water setup with plenty of plant cover or spawning mops. They’re egg scatterers—remove adults post-spawn if you want fry to survive.

Recommended Tank Parameters:

• Temperature: 72° - 80° F (22° - 27° C)
• pH: 6.5 - 7.5
• KH: 3 - 10 dKH
• Minimum Tank Size: 20 gallons (school of 6+ recommended)

Care Guidelines:

• Diet: Omnivorous. High-quality flakes, micro pellets, and occasional frozen foods.
• Social Behavior: Schooling. Keep in groups of 6 or more.
• Origin: Tank-Bred
• Adult Size: 2.5 – 3 inches (6.3 – 7.6 cm)
• Purchase Size: 1.25 – 2 inches (3.2 – 5 cm)

Sharp stripes. Smooth swimmers.
The Blackline Tail Tetra brings style, flow, and balance to any aquascape. Add this underrated standout to your tank today and watch your setup come alive.

Live Arrival Guarantee:

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