Black Skirt Tetra: The Ultimate Guide for Aquarists (2022)

The black skirt tetra is a freshwater fish that is tiny yet very intriguing. These fish love to live in shoals and are very peaceful by nature. Their black coat has a translucent, mesmerizing hue. The best part is that they are very easy to take care of and will thrive in most conditions.

These hardy fish are a favorite amongst aquarists, and it is no surprise that many love to pet groups of these fish. Black skirt tetras are happiest when kept in groups of five or more.

Don’t worry if you haven’t heard about these super lively fish before; we’ve curated the complete guide. And if you do know about them but do not have them as pets in your aquarium yet, we are pretty sure you’ll be convinced to get some once you finish reading this guide.

Our complete guide on black skirt tetras will help you understand these fish better, know how to care for them, and ultimately get some for your tank! Let’s get going!

Black Skirt Tetra

Facts Overview

Before we jump into details regarding black skirt tetras, let’s first go over this fish’s basic facts and specifications. This overview summarizes the details we are going to delve into later on. Let’s take a look:

  • Scientific name: Gymnocorymbus ternetzi
  • Species: G. ternetzi
  • Family: Characidae
  • Common names: Black tetra, black widow tetra, black skirt tetra, blackamoor, petticoat tetra, high fin black skirt tetra
  • Origin: Black skirt tetras are native to South America. They belong to the Characidae family, which is found in the river basins of Paraguay, Southern parts of Brazil, Bolivia, and Argentina.
  • Types: Normal black skirt tetras and sail-finned black skirt tetra.
  • Care and management: Hardy fish that are easy to care for. Very suitable for beginner aquarists.
  • Temperament/behavior: Peaceful by nature but do not do well with large fish and turn into fin nippers around them. They may turn slightly aggressive in that case.
  • Color: Silver, black, white
  • Size: Average size of 2 inches or 6 cm; may range in size from 1 to 2.5 inches
  • Maximum tank size: 15 to 20 gallons
  • Diet: Omnivorous by nature
  • Life cycle: 3 to 5 years
  • pH: 6.0 to 7.5
  • Temperature: 75°F-80°F (24°C-27°C)
  • Water Hardness: 5° to 20° dH
  • Breeding: Egg scattering
  • Tankmates: Bolivian Ram, Neon Tetra, Angelfish, Guppies, Molly, Dwarf Gourami
  • Diseases: May contract flukes, Ich, protozoa infections, and bacterial diseases
  • Preferred tank levels: Top and middle layers
  • Tank care: Freshwater with plantation and rock bedding

The Basics

Black skirt tetras or Gymnocorymbus ternetzi are community fish that do well in groups and get along great with other compatible fishes. Most fishes that belong to the Characidae family are usually bright and colorful, but black skirt tetras really do stand out, especially because of their black coats. They are quite popular and can be easily found in fish shops. These freshwater fish definitely stand out in the aquarium.

These hardy fish with beautiful gradients are excellent swimmers even though they are quite tiny compared to other fish. They thrive well with other types of tetras as well and survive for up to 5 years. Black skirt tetras are omnivorous by nature and accept a diet including plants, meat, or both.

Types of Black Skirt Tetras

Black skirt tetras have two main types:

  • Normal black skirt tetra
  • Sail-finned black skirt tetra

Out of these two, the sail-finned version is a rare find. Female fish are larger than males. Females may grow up to 2.5 inches, while males only grow up to 2 inches at most.


Black tetras live anywhere between 3 and 5 years in a freshwater tank. There have been reports of these fish living longer in a controlled and captive environment, but most of them do not. They are known to live up to 6 or 7 years in the wild. Nitrate levels and pH levels are usually factors that prevent these fish from living to their fullest in an aquarium.

Hygienic water conditions and a happy environment help these fish live long or at least complete their terms. It is best to keep them in groups of five or more to keep them happy. It is also better to keep them with compatible tank mates to prevent them from feeling lonely.

However, it is important to keep these fish away from other larger fish, especially ones that have flowy fins, as they tend to nip those. In turn, the larger fish can get aggressive and might kill off your tiny tetras. It is also important to provide black tetras with a balanced diet in order for them to remain healthy.

Physical appearance

Black tetras have a beautiful tetragonal shape since they are part of the Characidae family. The body tapers towards the back, while the front part is taller. Three very different yet gorgeous fins further add to their beauty.

The tail fin is thin, while the dorsal fin is small and square. The forked tail fin is not the only dramatic fin; the anal fin goes all the way from the stomach to the tail and gets narrower along the way. This is exactly what gives this fish a ‘skirt-like look.’ These translucent fins are mostly black or dark gray in color with rays.

The overall color of the fish is actually grayish-silver with a gorgeous gradient. The head region is paler in color compared to the abdomen and tail. Full-grown tetra fish are usually 1 to 2.5 inches and have two vertical black stripes at the front portion of their body.

The females are larger than males, while males have larger anal fins than females. As these fish grow and age, they start to get paler, and their color fades over time.

Care and management

Black skirt tetras are not super hard to care for and are largely available in the market since they are a great beginner’s fish. These hardy fish can live in versatile conditions and can be fed both plants and meat.

However, in order for them to thrive, it is smart to maintain the correct pH levels, nitrate levels, water hardness, temperature, tank size, and hygiene conditions in their freshwater tank at all times.

Tank size and requirements

Black tetras require a minimum of 15 gallons of water to be able to swim freely. These fish love to explore their habitat and are lovely swimmers. Plus, when kept in groups of 5 or more, they can only stay happy if they have enough space to move about easily.

A 20-gallons tank should be enough for them, or you could simply keep your black tetras with other compatible fish in an even larger tank. Gravel and darker sand substrates are best since they closely resemble the look of their natural habitat. Color is important since black tetras are not bottom feeders and will rarely go check out the kind of sand and gravel kept down there.

Black skirt tetras love to swim between tall plants, and the more of these you add, the better. The fish will have a fun time playing amongst plants in the tank. Adding dim lights can also be a great way for you to enjoy watching these playful fish, as this makes them seem more vibrant.

Driftwood, rocks, and caves can also be a great addition to the tank to spark that curiosity in your Tetras.

Kings Of The Aquarium

Water conditions

Certain water parameters are best suited for black tetras, and you must make sure you provide these water conditions if you really want your fish to thrive and remain healthy. It is a smart idea to replicate the water conditions that exist in their natural habitat, the river basins of South America in this case.

The water in these basins is slightly acidic and on the warmer side. Water conditions should be within the following parameters:

  1. Temperature: 70°F to 85°F, best-suited temperature lies in the middle of this range
  2. pH levels: Slightly acidic, ranging from 6.0 to 7.5
  3. Water hardness: 4 to 8 dKH
  4. Ammonia and nitrate levels: Low
  5. Water replacement: 25% to 50% change, twice a month

Although black skirt tetras are hardy fish, they live the longest when they’re provided with the parameters listed above. You can invest in a water testing kit to make this task simpler. Investing in a good water filter is also a great option. You could also purchase an aquarium heater to maintain the ideal water temperature.

Diseases and treatments

Even though black skirt tetras are hardy, they are prone to a few diseases, just like other fish. These include:

  1. Ich: This parasitic disease attacks your fish when it is under stress, especially due to poor water conditions. Ich is deadly and may kill off your fish if not dealt with in time. Although highly contagious, this disease is easily treatable. You simply need to isolate the affected fish from its group and treat it using a copper-based machine.
  2. Bacterial and fungal infections: Bacterial and fungal infections are also very common. Most black tetras show symptoms of Dropsy, fin rot, and fish fungus. These can be treated by suitable medications prescribed by a vet and improving water conditions.

Stress on fish can be reduced by:

  1. Maintaining hygienic tank conditions
  2. Flowing water parameters
  3. Adding adequate hiding spots and plants
  4. Keeping incompatible fish far away
  5. Simulating their natural habitat


Black skirt tetras are omnivorous by nature. They are almost happy with whatever you feed them, whether it’s plant-based or animal-based.

Nutrient-rich dry foods like flakes and pellets can be great choices for the main course. You may also experiment with frozen foods and live foods. Brine shrimps, bloodworms, blackworms, daphnia, and even tubifex can make great snacks.

Plants and algae are also other foods you can give your fish to snack on. Also, be careful of the amount you add. We recommend adding a quantity that they can eat within 5 minutes. This is a safe way to make sure you do not overfeed them.

Nature and temperament

By nature, black tetras are usually quite peaceful and curious. They do not get aggressive under most conditions, except when kept with incompatible tank mates. When placed around larger fish with flowy fins, they usually have the urge to go along and nip their fins, causing fights to break out. Betta fish and angelfish are the most common victims.

Otherwise, black tetras love to stay in groups, whether it’s with their own or with other compatible fish. These fish are also fast swimmers and curious explorers and love to tag along with their shoals.

Kings Of The Aquarium


As mentioned earlier, black skirt tetras are very compatible with all kinds of fish except those with flowy fins since they really attack and nip them without real cause. They should also not be around other fin nippers that are especially larger than them; otherwise, larger fish might nip the fins of your tetras. And if a bad fight breaks out, it could be fatal for your fish.

Groups of 5 or more are the best way to make a great shoal and to keep your fish happy. Even larger groups are recommended, as these make black tetras feel confident and comfortable in their surroundings.

So, what kinds of fish do black tetras go well with, and which ones are compatible? Let’s list them down!

Compatible tankmates

Below is a list of fish that are excellent freshwater tank mates for black skirt tetras:

  • Cardinal Tetra
  • Harlequin Rasbora
  • Dwarf Gourami
  • Neon Tetra
  • Celestial Pearl Danio
  • Honey Gourami
  • Chili Rasbora
  • Cory Catfish
  • Bolivian Rams

Incompatible tank mates

Apart from knowing fish that you can keep with black tetras, you should also know the species you should avoid keeping in the tank. Below is a list of incompatible fish:

  • Betta fish
  • Angelfish
  • Cichlids
  • Oscars
  • Goldfish


Breeding black skirt tetras is not very tedious, but it requires extra effort and certain criteria to make it work smoothly. Black tetras do not have a sense of attachment to their eggs or fish fry and can actually end up destroying them.

A separate fish tank is mostly required to make the breeding process successful. Most aquarists find that a 10-gallon tank is ideal for breeding. This separate tank meant for the babies should be built similar to the parent’s tank. All requirements and water conditions must be similar to the ones of the parent tank.

Additionally, what you really need to introduce as extras into the breeding tank are spawning mops, fake grass, and nets. Eventually, these will allow you to separate and keep the eggs safe from the fish.

Once you have everything set up, it is now time to breed. Go along with the following steps to successfully breed black tetras:

  • Look for a bonded pair in the main tank and separate them from the rest by placing them into the breeding tank. Live foods full of protein are an ideal diet for fish that are about to breed.
  • Male fish will chase the female around the tank once they are ready to breed. At this stage, all you need to do is make sure the male is simply not trying to attack the female. Keep them apart for some time if the male is looking for trouble.
  • Once breeding is successful, the female will start to look swollen. She will soon lay 1000 eggs in different places all over the tank. These eggs usually sink to the bottom, and since black tetras are not bottom feeders, you can easily create a barrier. This can be done by placing a net or mesh to separate the eggs and adults.
  • Once the process is complete, you must return the adults to the main tank. This will prevent them from feeding on their own babies and fish fry once they hatch.
  • Eggs usually hatch between 24 and 36 hours, and you can feed them powdered fish fry food or industrial as their first meal.
  • Just wait a few weeks, and then your fish fry will be able to eat foods like brine shrimp as well. Keep them separate at all costs until they grow big enough and won’t be victims of larger fish or their own parents.

Kings Of The Aquarium

Frequently Asked Questions

What fish go well with black skirt tetras?

Black skirt tetras are community fish that love to live in groups of 5 or more. They are the happiest in shoals as this makes them feel confident and comfortable. They also thrive well with certain other fish, given that they are not large and aggressive or ones with flowy fins.

Black tetras love to nip fins of fish such as angelfish and betta fish, but they can also become targets of nipping as well. Large fish that are fin nippers are a big no as well. Fish compatible with black skirts include:

  • Cardinal Tetra
  • Harlequin Rasbora
  • Dwarf Gourami
  • Neon Tetra
  • Celestial Pearl Danio
  • Honey Gourami
  • Chili Rasbora
  • Cory Catfish
  • Bolivian Rams

Are black skirt tetras hardy?

Yes, black skirt tetras are hardy fish. They can survive in versatile conditions and are popular as beginner fish. They are also readily available in markets all year round because of their popularity. They are also easy to care for and are great, peaceful, community fish. They thrive well with most other fish and live happily in shoals with their own kind as well.

To ensure they stay stress-free, healthy, and are able to live a long life, it is a must to imitate their natural habitat in your freshwater tank. Certain requirements and water parameters that you must provide them include:

  • A 15- to 20-gallon tank is best as these fish love to swim about and explore
  • Slightly acidic water with pH between 6.0 and 7.5
  • Temperature should be maintained between 70°F and 85°F
  • Water hardness should be between 4 and 8 dKH
  • Low nitrate levels should be maintained
  • Water should be changed twice a month with 25 to 50% replacement each time
  • Hygiene should be a priority
  • Adequate hiding spots and plants should be placed to keep fish stress-free

How many black skirt tetras should be kept together?

It is usually recommended to keep at least 5 black tetras together. This helps them feel confident and comfortable in their surroundings. Larger shoals are also great as this can help the fish feel less isolated due to the mimicry of their natural habitat. Black skirt tetras can also be kept with other compatible fish.

How long do black skirt tetras live?

In their natural habitat, black skirt tetras are known to live for 6 to 7 years. In a controlled environment such as an aquarium or freshwater tank, they live for longer than that. To make sure they complete their average span of 3 to 5 years, it is a must to maintain suitable tank conditions. If you are really vigilant, yours might just survive a tad bit longer.

Do black skirt tetras need a filter?

Black skirt tetras do not have special filter needs. A HOB or hang-on-back filter is typically enough. If your tank is larger, a canister filter might be a suitable option as well. This generally causes more harm than good, so it is up to you to decide the filter you need.


We hope this article has convinced you to go get your very own black tetras to keep as pets. We also hope that once you do purchase some, our guide will help you care for them in the best way possible! Best of luck!