Tetras lay eggs; they are not livebearers. The female tetra will scatter her eggs all over the tank. The male tetra will then fertilize the eggs by releasing his milt into the water. A female tetra will lay around 50 to 130 eggs, out of which 30 to 40 will hatch in 24 hours after fertilization.
Let’s now see in detail how and when tetras lay eggs.
How Do Tetras Lay Eggs?
Tetras lay eggs by performing the “mating dance.”
During the mating process, the male tetra will approach the female by swimming around her in a squarish pattern.
He will move in short and jerky movements with pauses in between.
If the female gets impressed, she’ll begin swimming beside the male and will eventually lay anywhere from 50 to 130 eggs all over the aquarium.
These eggs are small, clear, and a bit sticky. So they easily attach to the sand and rocks in the aquarium.
The male tetra will then release his milt into the water to fertilize the eggs.
Depending on the water temperature and tetra species, the eggs can take up to a day to hatch.
However, do keep in mind that not all eggs will hatch. Only around 30 to 40 eggs will hatch.
After hatching, the tetra fry will keep feeding on their egg sack for the first couple of days.
After that, in about four days, the tetra fry will start swimming freely.
At this time, the tetra fry will try to avoid getting eaten by their own parents.
So they will hide under plants or rocks until they grow big enough to avoid getting eaten.
That’s why it’s better to provide plenty of hiding spots in the aquarium.
How To Know When Tetras Are About To Lay Eggs?
It can be difficult to determine whether or not your tetra is about to spawn simply because they all look approximately the same.
To make matters worse, many aquarium owners are unlikely to notice when their tetras are carrying eggs if they don’t know what to look for.
Given below are some of the ways to know when your tetras are about to lay eggs:
- One way to identify if female tetras are about to lay eggs is to just look at their bellies. If their bellies are swollen, then the chances are that they are ready to spawn. However, a slight swelling around these parts could also be a result of overfeeding.
- Yet another way to spot a female tetra who is about to spawn is by turning the light on an hour early prior to feeding the fish. This way, you will be able to see if the tetras are courting or spawning in the community tank.
- Tetras tend to lay their eggs in the morning. So, you must ensure a dark tank for at least 12 hours before introducing some light into it. Light usually makes the tetras think it’s daybreak, and they will start the egg-laying process if they are ready to do it.
- Tetras don’t drop their eggs unless the water conditions are favorable. So, you can put them in a separate breeding tank to see if they are ready to spawn.
How Do Tetra Eggs Look Like?
Tetra eggs are smaller than one millimeter spherical-shaped balls. They are white or yellow in color, transparent, and a little bit sticky. However, not all eggs are sticky. If there’s a small black dot inside them, it means they are fertilized.
After the eggs are laid, the sticky ones will attach to plant leaves, moss, etc., and the non-sticky ones will float to the bottom of the tank.
These eggs are very difficult to see through the naked eye. However, a flashlight makes it easy to spot them.
How Often Do Tetras Lay Eggs?
In the wild, a pair of tetras will usually spawn every 14 days approximately.
They spawn so frequently in the wild because they have access to a lot of food and water, so they don’t have to worry about survival.
As a result, they can devote themselves to spawning without any worry.
However, it’s a big challenge to breed tetras in captivity. So it’s difficult to predict how frequently they can lay eggs in captivity.
One thing that you can predict though is that the female tetras will lay around 50 to 130 eggs at a time.
Out of these, only around 30 to 40 will hatch to produce tetra fry.
How Long Does It Take For Tetras To Lay Eggs?
Tetras depend a lot on their habitat and water conditions for their health, gestation period, and other things.
If tetras are not kept in proper water conditions, they will get stressed, lose their color, fall ill, and even stop breeding. However…
If the water conditions are favorable, tetras will lay eggs every 14 days approximately.
The gestation of tetras is identical to other tropical fish like mollies and guppies.
However, the main difference is that tetras are not livebearers.
So the female tetras carry eggs in their ovaries instead of fry.
How Long Does It Take For Tetra Eggs To Hatch?
Once the eggs are fertilized, it will take about two days for the fry to hatch.
The young tetra fry will be tiny and not able to swim freely at first. They will feed off of their egg sack for a couple of days.
Then depending on the tetra species and water temperature, the tetra fry will start swimming freely in about four days.
Where Do Tetras Lay Eggs?
Once the female tetras lay their eggs, the eggs stick on the plant leaves, moss, or at the bottom of the tank on the substrate.
However, you won’t find the eggs at one place in the aquarium. Instead, they will be scattered throughout the tank.
Moreover, since the eggs are transparent, they might look like waste to beginner aquarists.