How Can You Tell If A Black Skirt Tetra Is Pregnant? {Breeding & Spawning Tips}

Black skirt tetra is one of the most colorful species of aquarium fish. How can you tell if a black skirt tetra is pregnant?

Black skirt tetra exhibits a lot of exclusive features, including their breeding pattern. They show some distinct characters when they are ready to lay eggs, and aquarists often lookout for signs.

Let’s find out the signs and strategies we use to find out if black skirt tetras are pregnant.

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How Can You Tell If A Black Skirt Tetra Is Pregnant?

Black skirt tetras are not livebearers, they lay eggs. The eggs in a bag-like space will be visible in the fish.

  1. When they are ready to lay eggs, a female black skirt tetra becomes bulgier and fatter.
  2. You will also find a dark spot around the belly of the fish, somewhere close to the tail.

Aside from the physical body changes in black skirt tetra, they can also exhibit some behavioral changes. The eggs of the black skirt tetra are fertilized externally by the males after they are out of the females.

How Can You Tell If A Black Skirt Tetra Is Pregnant

Is My Black Skirt Tetra Male or Female?

Before we talk about the breeding itself, it is first essential to learn how to differentiate between the two sexes of the fish. The major between the male and the female sexes of black tetra is that:

  • males usually have smaller and more elongated bodies than females.
  • females are plumper than males.
  • sometimes, male Black Skirt tetras will have white spots on their caudal fin.

The black skirt tetra is not livebearers, they lay eggs. They are also free spawning fish because of their egg scattering behavior. Black skirt tetra shows no parental care for their fry, and they don’t protect their eggs as well.

Black Skirt Tetra Breeding

When you notice that your black skirt tetras are approaching the breeding stage, you need to set up a spawning aquarium.

The spawning aquarium will:

  • provide functional space to favor the breeding of black skirt tetras.
  • protect the pregnant fish as well as their eggs.

You will first introduce the black skirt tetra to the tank and watch out till when they lay their eggs before adding the male later on. You should, however, ensure that the water in the breeding aquarium should be mature, well-aerated, and unadulterated.

You can also allow the eggs to fall through by adding:

  • mesh
  • marble layer
  • plastic grate

You should ensure that the adults do away from the eggs, lest they eat the eggs when the breeding is over.  You can also add plants and some other surfaces where the eggs can attach.

Breeding Behavior Of Black Skirt Tetra

You can start noticing the breeding behavior in black skirt tetra when you start seeing the fish in pairs.

This pairing starts about 7-10 days before the breeding begins appropriately.

Once you notice this pairing, you should consider separating them into the spawning aquarium tank.

The pairs separate themselves from the school and move together, and you will also notice that the pairs feed heavily on live and frozen foods. You should increase their feeding quality and quantity at this stage. They need more supply as they edge closer to their spawning period.

YouTube video

Black Skirt Tetra Spawning

During the spawning time, they become fatter with brighter colors. You should also introduce the female one night before the male. Once the male sight these breeding signs in females, they start chasing the females around the tank.

However, you might have to separate their tank if the chasing becomes overaggressive. You can then reintroduce the male to the tank after a while.

How Many Eggs Do Black Skirt Tetras Lay?

If the spawning goes as it should be, the females are capable of laying up to a thousand eggs. The eggs can be scattered all over the tanks over the surfaces of the tanks and planes. Some of the eggs can also fall to the bottom of the tank.

Once the females lay eggs and release milts, the next thing is to evacuate both the male and female from the spawning tank. This separation is necessary because adult black skirt tetra can eat their eggs. The eggs will then begin to hatch into fry after 24-36 hours.

Suitable Tank Mates For Keeping Black Skirt Tetras

Black skirt tetras are not very aggressive and are not peaceful at the same time. They, however, have semi-aggressive behaviors towards tank mates that have long fins. They exhibit nipping behaviors towards species like bettas and angelfish.

However, smaller fish like danios, rasboras, dwarf cichlids, and other smaller fish can live peacefully with black skirt tetra. It is not advisable to keep them with other aggressive fish like tiger barbs and bettas. You should also ensure that the tank is not overcrowded.

How To Protect Black Skirt Tetras

It is best to provide a lid for a black skirt tetra’s aquarium because they are excellent jumpers. If their aquarium is not covered, they can jump out of the tank, which can cause severe damage to them.

You are keeping the water parameters of the black skirt tetra tank at an optimum level to ensure adequate growth, proper breeding, and overall well living standard. You should also equip their aquarium with:

  • plants
  • floating wood debris
  • rocks

The presence of these matters will provide black skirt tetra with a hiding place and where to rest. They also thrive in the temperature range of 75-80°C, and varying temperature can be detrimental to their health. They also prefer neutral pH levels in their tank.


Black skirt tetras are one of the most prolific aquarium species when it comes to breeding. They are non-live bearers. Hence, black skirt tetra lay eggs rather than give birth to their young ones alive.

They are capable of laying up to 1000 or more eggs at one spawning cycle. They also show some apparent signs that show when they are about to lay their eggs.

Aquarists must take certain precautions when black skirt tetras are pregnant and about to spawn. Therefore, these precautionary measures necessitate them to know the signs that pregnant black skirt tetras show before they lay their eggs.


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Hello, I'm Jason. I'm the guy behind I volunteer at my local fish shop and I created this site to offer tips and advice on the fish I care for.