Black Skirt Tetra

Species NameGymnocorymbus ternetzi
Common NameBlack Skirt Tetra
Care LevelBeginner to Intermediate
Lifespan3-5 years
Adult Size2.5 inches
Minimum Tank Size15 gallons
Temperature70°F – 80°F (21°C – 27°C)
Water ConditionspH 6.0-7.5, Soft to medium hardness

About the Black Skirt Tetra – Species Summary

Originating from the tranquil waters of South America, the Black Skirt Tetra, scientifically known as Gymnocorymbus ternetzi, has become a staple in the aquarium hobby. Their elegant “skirt-like” fins combined with a distinct black vertical striping pattern make them a captivating sight, effortlessly darting around in aquariums worldwide. Given their hardy nature and beautiful display, these freshwater fish serve as both an ideal candidate for beginner aquarists and a rewarding experience for seasoned enthusiasts.

Although they are native to the calm streams and rivers of Brazil, Argentina, and Bolivia, the adaptability of Black Skirt Tetras to various water conditions is a testament to their resilience. Their schooling behavior, combined with their undemanding nature, makes them not only a visual delight but also an active participant in maintaining a dynamic aquatic environment.

Black Skirt Tetra Lifespan

Black Skirt Tetras can live up to 3 to 5 years in captivity, with some even reaching the upper end of this spectrum when given optimal care. Their lifespan largely depends on factors such as water quality, diet, and overall tank conditions. When provided with a well-maintained environment, these fish not only live longer but also exhibit more vibrant colors and display more active behaviors.

Routine water changes, a balanced diet, and regular monitoring for potential health issues are essential factors that contribute to the longevity of Black Skirt Tetras. With their moderate lifespan, they serve as long-term companions, bringing consistent vibrancy to any aquarium.


The Black Skirt Tetra boasts a silver-grey body adorned with two striking black vertical bands. Their most distinguished feature, however, is their long flowing “skirt-like” anal and dorsal fins. These fins, combined with their unique banding pattern, make them instantly recognizable.

There are also other selectively bred variations of this species, including the “long-fin” and “white skirt” types, which have been developed to cater to hobbyists’ desires for diverse aesthetics within the same species.

Average Size

Typically, Black Skirt Tetras grow to an average size of 2.5 inches when fully mature. The females might appear slightly more rounded, especially during breeding times, while males possess a more streamlined physique.

Black Skirt Tetra Care

Tank Size

A minimum tank size of 15 gallons is recommended for Black Skirt Tetras. Given their active nature and preference for schooling, having ample space allows them to swim freely and display their natural behaviors.

How To Set Up Their Tank

When setting up a tank for Black Skirt Tetras, it’s essential to emulate their natural environment. A substrate of fine sand or soft gravel works best. Incorporating live plants, especially those with broad leaves like Anubias or Java Fern, can create hiding spots and resting areas. Driftwood and rocks can also be used to add structural complexity.

Lighting Requirements

Black Skirt Tetras don’t have specific lighting requirements. A standard aquarium light that supports the growth of live plants and highlights the fish’s natural colors will suffice. However, it’s always a good idea to have a period of darkness, replicating the natural day-night cycle.


For Black Skirt Tetras, a pH range of 6.0 to 7.5 is ideal. Regular testing can ensure the pH remains stable, providing a consistent environment for the fish.


Maintaining a temperature between 70°F and 80°F (21°C to 27°C) is crucial. While they are adaptable, sudden temperature fluctuations can stress the fish. Using a heater and monitoring the temperature can prevent such issues.

Water Parameters

Soft to medium water hardness is ideal for Black Skirt Tetras. Regular water changes and testing for ammonia, nitrites, and nitrates ensure a healthy environment.

Disease Potential

While they are generally hardy, Black Skirt Tetras can be susceptible to common fish diseases like Ich or fin rot. Regular inspections, quarantine of new tank additions, and maintaining water quality can prevent most disease outbreaks.

Food & Diet

Being omnivores, Black Skirt Tetras thrive on a varied diet. High-quality flake food or micro pellets serve as a staple, but it’s essential to supplement this with live or frozen foods like brine shrimp, daphnia, or bloodworms occasionally.

Behavior and Temperament

Black Skirt Tetras are peaceful and are best kept in schools of six or more. They display intriguing schooling and shoaling behaviors, especially when they sense potential threats. They predominantly occupy the middle regions of the tank.

Tank Mates

Due to their peaceful nature, Black Skirt Tetras can coexist with a variety of tank mates. Suitable companions include Corydoras, smaller Rasboras, and other Tetra species. It’s essential to avoid aggressive or fin-nipping fish.


Breeding Black Skirt Tetras in captivity can be challenging but rewarding. When conditions are optimal, females will lay eggs among plants, which males will then fertilize. After spawning, it’s advisable to remove the parents, as they might consume the eggs. The eggs typically hatch within a day, and the fry becomes free-swimming in about four days, ready to be fed infusoria or finely crushed flake food.

Black Skirt Tetra FAQs (Frequently Asked Questions)