How To Tell If You Have Pregnant Neon Tetra

How To Tell If You Have Pregnant Neon Tetra7 mins read

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How to tell if you have pregnant neon tetra

If you are wondering how to tell if you have pregnant Neon Tetra, you’re probably not alone. Fish pregnancy and reproduction are surprisingly complex subjects.

Indeed, it is very often that new fish owners suddenly find themselves with more fish on their hands than they bargained for!

These small schooling fish breed relatively easily, especially if they feel safe, comfortable, and well cared for in their tank environment. So, read on to understand the ins and outs of Neon Tetra pregnancy, how to spot it, what neon tetra eggs look like, and much more…

How To Tell If You Have Pregnant Neon Tetra

Once you know what you’re looking for, it’s not hard to spot pregnant Neon Tetras. The main things that mark them out are their appearance and behavior, both of which change compared to fish that are not carrying eggs.

1. Observe Changes In Appearance

When they become pregnant, Neon Tetras change their appearance significantly. The biggest thing to notice is the rounded abdomen where they are carrying the eggs.

Later on, this article outlines some common diseases you may confuse this with. However, a good rule is that the abdomen of a pregnant Tetra may stick out very far from your fish’s body, much more than with disease. This can be almost the same distance as your fish’s height from its back to its stomach. This can make them unmistakable.

Look At Your Fish From Above

If in doubt, look at your fish from above. Due to the huge number of eggs that female Neon Tetras carry, you will also be able to see her abdomen sticking out from either side of her body.

Author’s Note: At this stage, it’s very easy to differentiate the females from the males. In addition, if you think your fish may be pregnant but you are not sure, checking on how they look from above each day can help you see noticeable changes in their size and shape.

2. Observe Behavioral Changes

Another surefire way of telling whether your Neon Tetra is or is not pregnant is behavioral changes. Neon tetras are generally bold fish, so any tetra that hides away tends to have a major change going on.

This could be illness, but it can also be pregnancy. Pregnant fish may especially seek out shelter to look for a place to lay their eggs.

Pregnant Neon Tetra Appetite

Appetite can change when your Neon Tetra is pregnant, in more ways than one. Due to the multitude of different hormones coursing through your fish’s body, your tetra will eat more or less.

This is normal, but the same rules of feeding apply. Never over or underfeed a fish, always remove uneaten food after five minutes, and ensure all fish are getting food without any bullying.

However, neon tetra pregnant females may need extra protein for energy. Your female may seem especially hungry, for example, swimming up to the surface of the water.

If this is the case you can occasionally add a bit of frozen protein. A good example is aquatic invertebrates such as brine shrimp which will help her get some more energy.

3. What Factors Cause Neon Tetras To Become Pregnant?

Factors cause neon tetras to become pregnant?
The effects of seasonality are still relatively unknown even though these are one of the most popular captive-bred fish and are often raised in large farms.

Neon tetras, like many other bony fish, are ovoviviparous. This means that they grow their eggs inside their body and then spawn, laying them so that the male can fertilize them.

This is in contrast to livebearing fish like mollies, platies, guppies, and swordtails. These fish give birth to live, free-swimming fish fry. Therefore a pregnant neon tetra is one that is carrying eggs.

Fish do not need a male to grow the eggs in their uterus, but they do need one to fertilize them. This process, unlike with livebearers, happens outside their body.

But what causes these eggs to start growing? Scientists have not fully studied this process. Nevertheless, factors such as lighting, temperature, and other tank conditions all play a complex and interconnected role.

  • Lighting

Neon tetras do not like bright lighting at all!

This is because in the wild their forested habitat is relatively shadowed by large rainforest trees. In captivity, they can survive under bright lights, but they won’t thrive. If you want to breed your fish, it’s best to recognize that they are most likely to become pregnant in optimum conditions.

  • Temperature

A relatively high temperature like 78 F (26 C) is optimal for Neon Tetras to spawn. In the wild, Neon Tetra spawning is seasonal. In captivity, the lack of cues indicating the changing of the seasons leads them to spawn at any time of year depending on whether or not other triggers are present.

However, a higher water temperature that mimics this process doesn’t hurt. Thus, you may sometimes find raising the temperature of your tank a bit triggers tetras to become pregnant. If other conditions are right, it can even to start the mating and courtship rituals.

  • Seasonality

The effects of seasonality are still relatively unknown. This is despite the fact these are one of the most popular captive-bred fish and are often raised in large farms.

However, like with any fish that mates on a seasonal basis, generally, conditions similar to the rainy season are what can influence pregnancy in Neon Tetras. Taking into account their Amazonian habitat, this includes heavy falling rain, heat, and humidity.

Author’s Note: There are no hard and fast studies of the effects of mimicking these on tetra pregnancy and breeding success, but if you want to experiment, it’s always possible to increase the filter flow rate slightly or buy a bubbler to increase oxygenation of the water in the same way that heavy tropical rains would do so in the wild.

What Factors Cause Neon Tetras To Give Birth?

What factors cause neon tetras to give birth?
A pregnant Neon Tetra will be courted by the available males until she shows responsiveness and drops her eggs for him to fertilize. Pictured is a male fish.

The presence of an eligible male is the biggest factor that causes Neon Tetras to give birth. The available males will court a pregnant Neon Tetra until she shows responsiveness. At this stage she will drop her eggs for him to fertilize.

A safe tank environment also encourages all your Neon tetra’s natural behavior. Superficially, they can give birth with other tankmates such as other kinds of tetras in the tank. However, a separate breeding tank makes them feel more secure.

However, this process is also connected with the factors that control egg creation. These include things such as seasonality, temperature, and lighting, as well.

Author’s Note: The mating dance of the Neon Tetra is great to watch if you are in the right place at the right time. You can see the male chase the female and the pair swim elegantly through the water. This may look like chasing, but generally, there is no nipping or aggression. Instead, the male simply encourages the female to drop her eggs so he can fertilize them.

Common Confusions With Neon Tetra Pregnancy

Common confusions with neon tetra pregnancy
Neon tetras are omnivorous and feed a mixture of flake or pellet food as well as fresh or frozen protein and the occasional bit of vegetable matter is best for them. Image from Flickr

Unfortunately, there are still a few diseases that you can mistake for pregnancy. This is especially in small fish like Neon Tetras, whose needs can be less easy to read than larger ones like goldfish. Read on for some of the main ones to know about:

1. Dropsy

Sadly, if your fish has dropsy, there’s generally not much you can do about it. Sadly, in general, this disease tends to be fatal. Treatment isn’t really possible, especially once your fish begins to show body changes.

However, it’s worth knowing how to identify it during pregnancy. Dropsy is especially notable as all your fish’s scales will stand out like a pinecone. Your fish will also show other signs of illness, such as trouble staying afloat and lethargy. In addition, they won’t have appetite.

On the other hand, a pregnant Neon Tetra may show an increased appetite. In addition, she certainly won’t have scales that stand out. Dropsy, like other bacterial infections, comes from poor water quality. If you want to prevent Neon Tetras from dying, it’s best to maintain good water quality.

2. Bloating

Bloating can arise from issues other than Dropsy. For example, one of the most common issues that causes bloating is overfeeding. Overfed fish may also have digestive issues.

It helps not to over or underfeed your fish. Overfeeding fish means food builds up in their digestive tract. Overfeeding generally happens when you feed fish more than once a day. Problems really start to arise when you don’t clean up any food that is still left uneaten after five minutes.

Bloating can also happen if you don’t feed a balanced enough diet and instead only feed fish flakes. These have a good nutrient balance but are processed and thus can be hard to digest. Likewise, this can happen if you feed pellets that are too dense and indigestible for your fish.

3. Digestive Issues

Apart from bloating, other digestive issues can arise such as constipation. Alternatively, your fish’s digestive system may be overactive. Sometimes this can come from disease, for example from a bacterial infection, but sometimes it can come from feeding the wrong food.

Neon tetras are omnivorous and feed a mixture of flake or pellet food as well as fresh or frozen protein and the occasional bit of vegetable matter is best for them. No fish can live on flake or pellet food alone!

4. Other Diseases

Other diseases may not cause the larger rounder appearance that is common to pregnancy, but they can cause behavioral changes in your fish that you can easily mistake for pregnancy.

Pregnant fish can and do lose energy, swim with difficulty, and hide, very similarly to sick fish. However, they won’t show the same obvious signs of illness that a sick fish will show. Furthermore, unless your pregnant fish is also sick, a pregnant Neon Tetra should still have bright eyes, shiny colors, and should not seem too lethargic or listless.

Generally, if a fish is sick as opposed to pregnant its symptoms will get gradually worse. They generally also will be present all the time.

On the contrary for a pregnant fish, lethargy may improve after feeding. With experience, you will be able to tell the difference between sick and pregnant fish.

How To Look After A Pregnant Neon Tetra Properly

How to look after a pregnant neon tetra properly
Keeping a close eye on your Neon Tetra’s behavior is a good way of checking that everything is going according to plan with the pregnancy. A healthy Tetra will have bright eyes and colors like the one pictured.

Neon tetras are hardy fish. However, they still need attention, just like more sensitive species do. Keeping a close eye on your Neon Tetra’s behavior is a good way of checking the pregnancy is going well.

How To Tell If Your Pregnant Neon Tetra Is Going To Lay Eggs?

There are no hard and fast rules about when a pregnant Neon tetra will lay eggs. However, you may begin to notice behavior such as hiding in and amongst plants. You will also see your fish looking for a safe place away from tankmates.

Female Neon Tetras will often choose plants or driftwood to lay their eggs on or nearby. These provide shelter for them, ensuring that the eggs don’t get eaten by predators.

What Do Neon Tetra Eggs Look Like?

If you are wondering ‘what do neon tetra eggs look like’, don’t worry.

Neon tetra eggs can be hard to spot! They look like very small, clear, round balls. You may see them hanging off the stems of planta or the undersides of plant leaves, or, alternatively, on the glass of the aquarium tank.

How To Tell If Neon Tetra Eggs Are Fertilized?

Luckily, it’s easy to tell when Neon Tetra eggs are fertilized. The small, crystal-clear balls will turn an opaque white.

Bottom Line

Neon Tetra Eggs
Neon tetras are easy fish to breed, and as a result, this is one of the most popular species for beginner aquarists both to keep and to breed, meaning that if you are careful, you will soon have many more fish on your hands.

In the end, it’s not really too hard to tell whether you have pregnant Neon Tetra or not. However, once your fish are pregnant, you know what to do.

Neon tetras are easy fish to breed. As a result, this is one of the most popular species for beginner aquarists both to start off with. This means that if you are careful, you will soon have many more fish on your hands.

Frequently Asked Questions

Are Neon Tetra Fish livebearers?
No, Neon Tetra fish are not livebearers. It's easy to see why they might be confused for livebearers such as guppies, however, due to the fact that the word pregnant is used for both reproductive processes. However, there’s a real difference between fish that give birth to live young like guppies, and the Neon Tetra, which lays eggs that are fertilized externally. For starters, there is much more of a risk of death of the mother in livebearing fish. Fortunately, with Neon Tetras, this is one issue you won’t have to face.
Are Neon Tetras Easy To Breed?
Yes, - fortunately Neon Tetras not only are free from the pregnancy complications of livebearing fish like guppies and mollies, but they are also one of the easiest species of small schooling fish to breed. Indeed, they have already been bred in captivity for a long time. It’s best to keep the fish you wish to breed in a separate breeding tank at a temperature of 72 F/ 22 C. This is in contrast to the Cardinal Tetra, which looks very similar to the Neon Tetra but has not had this history of captive breeding and thus is much more sensitive.
How Do I Tell Male And Female Neon Tetras Apart?
Unfortunately, it’s very hard to tell male and female Neon Tetras apart. In fact, one of the best ways of telling is when the female fish actually gets pregnant. At this point, you will notice her rounded stomach and behavioral changes. It’s also possible to identify the females when the males are chasing them during courtship.
Do Neon Tetras Die After Laying Eggs?
You may have heard that Neon Tetras die after laying eggs and have thus readied yourself for the worst. The truth is, Neon Tetras can actually live for up to ten years in the wild. It is the popularity and ready availability of the species that means many beginner aquarists care for tetras without knowing how to get them their maximum lifespan and as a result, the species has developed a reputation for dying easily. If tetras die after something that uses a lot of energy like breeding, it generally means that they didn’t have enough energy or nutrition in the first place, or something else, like disease or poor water quality, was affecting them.
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Tal Halperin

Tal is an avid fish keeper and has been raising ornamental fish for decades. As a little boy, he drove his father crazy to buy him an aquarium with all the necessary equipment. Now, after a career in the field, he has set up Your Aquarium Place to offer the most comprehensive guide to ornamental fish keeping available and share his passion for the different species he has looked after.