The Weitzmani Tetra (Hemigrammus weitzmani), also known as the Black-Wedge Tetra, is a unique and visually captivating species admired for its bold black markings, contrasting white highlights, and shimmering body. At around 3cm, this small tetra makes a big impression with its distinctive coloration and calm, schooling behavior. Native to the blackwater tributaries of the upper Rio Negro basin in South America, the Weitzmani Tetra thrives in soft, acidic water and planted aquariums. While somewhat rare in the hobby, it's a prized choice for aquarists looking to showcase a peaceful, yet exotic freshwater community.

🐠 Key Features:

• Scientific Name: Hemigrammus weitzmani

• Common Name: Weitzmani Tetra, Black-Wedge Tetra

• Size: ~3cm (maximum 4cm)

• Lifespan: 3–5 years

• Temperament: Peaceful, social

• Difficulty Level: Moderate

• Origin: Rio Negro basin, South America

• Best kept in groups of 6 or more

🌊 Water Conditions

Weitzmani Tetras do best in soft, slightly acidic water with stable conditions:

• Temperature: 23–27°C (73–81°F)

• pH: 5.5–7.0

• Hardness: 1–8 dGH

• Tank Size: Minimum 15 gallons for a small school

• Water Type: Freshwater; prefer blackwater-style tanks

• Filtration: Gentle flow, sponge filter or low-flow HOB filter

• Lighting: Dim to moderate; subdued lighting helps highlight their colors and mimic natural habitat

Add driftwood, Indian almond leaves, and live plants to replicate their blackwater environment and reduce stress.

🧍‍♂️ Tank Mates

Weitzmani Tetras are peaceful and non-aggressive, making them suitable for community tanks with similarly tempered species.

Compatible tank mates include:

• Small, peaceful tetras (e.g., Ember, Neon, Glowlight)

• Dwarf Rasboras

• Corydoras Catfish

• Otocinclus

• Peaceful dwarf cichlids (e.g., Apistogramma)

• Freshwater shrimp (if size difference is appropriate)

Avoid:

• Fin-nippers

• Large or aggressive species

• Boisterous fish that may outcompete them during feeding

Always keep them in groups of at least 6–8 to reduce shyness and encourage natural schooling behavior.

🍽️ Feeding Habits

Weitzmani Tetras are micro-predators in the wild, feeding on tiny invertebrates. In aquariums, they thrive on a varied omnivorous diet:

• High-quality micro pellets or flakes

• Live or frozen foods like daphnia, bloodworms, and brine shrimp

• Crushed freeze-dried options

• Occasional plant-based foods (spirulina flakes or algae tabs)

Feed them small portions twice daily, ensuring all food is consumed within a few minutes to prevent waste buildup.

🧼 Care and Maintenance

• Perform weekly water changes of 25–30%

• Use a soft sponge filter or pre-filter to avoid suction-related injury

• Monitor water quality regularly—ammonia, nitrite, and nitrate should remain in check

• Avoid sudden temperature or pH swings

• Use a tight lid—like many small tetras, they may jump when startled

Being slightly more sensitive than common tetras, they require consistent water quality and a stress-free environment to thrive.

🌿 Why Choose the Weitzmani Tetra?

The Weitzmani Tetra is a striking addition to any peaceful freshwater setup. Its bold appearance, graceful movements, and compatibility with softwater community tanks make it a standout choice for aquascapers and collectors alike. Though slightly rarer and more delicate than your average tetra, its elegance and unique charm are worth the care.

Elevate your aquarium with the Weitzmani Tetra—order yours today and experience the beauty of blackwater aquatics!