Neon Green Tetra (Paracheirodon simulans): Care guide in the aquarium

The Neon Green Tetra is a very beautiful freshwater fish that we love. While many people flock to the standard Neon Tetra, this species has a lot to offer as well.
In general, they are beautiful fish that are quite easy to care for. They also have some subtle variations that can be fun for aquarists looking for something a little different (without going too wild).
Because of that, we wanted to put together a guide that highlights this amazing fish and how to care for it. We think the Neon Green Tetra deserves as much attention as the other popular tetras you see in tanks everywhere.
Let’s make it happen!
Species Summary
The Neon Green Tetra (Paracheirodon simulans) is a fish that is often confused with its more popular relatives. Another common name for them is False Neon Tetra due to this common misidentification.
While there are some physical differences that we’ll delve into a bit more, there are also a lot of similarities. This becomes clear when comparing diets or general temperament. This is also why we are hesitant to say that there is a clear “winner” when it comes to the popular tetra species.
In the wild, you can find these fish mainly in the Amazon River basin in South America. The Negro and Orinoco rivers are the most popular bodies of water where you will find them, but they have been known to stray a bit from time to time.
They tend to prefer calm blackwater areas that have large trees, vegetation, or debris nearby. This means that the water they are used to is quite acidic and doesn’t get much light (more on this later). Tributaries with a sandy substrate are a common hotspot for the Green Neon Tetra.
Life expectancy
The lifespan of the Neon Green Tetra is around 2 to 3 years. This is shorter than its more popular counterparts.
Like any fish, the lifespan of a Neon Green Tetra can easily be influenced by its quality of life. A good diet, proper tank setup, and good water will help them live longer. If you neglect them, the opposite is true.
Appearance
The appearance of the Neon Green Tetra is something that puzzles many people. This is why these fish are so often misidentified.
From afar or at first glance, they look a lot like the basic Cardinal Tetra or Neon Tetra. His body shape and teal primary color are almost exactly the same!
At first glance, it can be hard to tell the difference between these fish and their more popular relatives.
The difference when it comes to color is when you start looking at red. While it is present, it is much less visible (sometimes barely noticeable). To go along with it, the blue-green area of their bodies is much more vibrant and generally brighter.
This combination makes the green coloration the most dominant and gives them their name.

Some of these fish may have more red spots than others, making them even harder to tell apart in direct comparison. We’ve found that it’s usually easiest to identify neon green tetras when they’re on a sandbar (which they prefer). There’s something about having a bunch of them together that really makes the green pop!
Size
The average size of the Neon Green Tetra is around an inch long when fully grown. This makes them slightly smaller than their close relatives.
Size is something that can be influenced by genetics or quality of care (especially during the developmental years). While it may be difficult for us to tell a difference in something so small, it is something to pay attention to when assessing the health of a fish you wish to purchase.
Tetra Neon Green Care
Neon Green Tetra care is not very challenging. There are some important principles that you must follow if you want them to thrive, but this species will not hold you back.
All you need to do is stick to the guidelines listed below and be consistent. An unmotivated or careless aquarist who knows everything about a fish is always worse than a diligent owner with average knowledge!
tank size
The recommended tank size for the Neon Green Tetra is around 15 to 20 gallons (we prefer 20). While some aquarists keep these fish in tanks as small as 10 gallons, we think that’s insufficient.
The reason for this is that you won’t get just one of these little critters, you’ll get a whole school of at least 6-8. This is necessary for them, which means you have to make sure there is enough space for everyone!
Author’s Note: We have seen some people say they have kept Green Neon Tetras in 5 gallon tanks. This is NOT a good idea and will ultimately harm the health and happiness of your fish. Never put them in such a small tank!
water parameters
The main thing you want to remember when it comes to water parameters and the Neon Green Tetra is consistency. These fish are quite durable and have reasonable level windows, but can suffer health issues if level changes occur.
- Water temperature: 75°F to 85°F
- pH levels: 5 to 6.5
- Water hardness: Very soft
To maintain the quality of the water, it is necessary to carry out partial water changes of approximately 25% weekly. You should also test your water parameters regularly with a reliable test kit (especially early on on your property).
What to put in your tank
It is important to mimic the Neon Green Tetra’s natural environment as much as possible. This will keep your stress levels down, which can have a huge impact on your overall health (and is simply a good thing to do for your fish).
A sandy substrate is a no-brainer since its natural habitat has it exclusively. We’ve heard of some owners testing gravel for convenience with other tank mates, but that’s not ideal.
You’ll also want to add some greenery and debris/decorations. These fish are used to this and use them as places to hide and feel safe. Driftwood, plants like hornwort or water wisteria, and rocks are great places to start.
Author’s Note: Make sure the water flow in your tank is kept at a reasonable level. These fish are not used to high current environments and will suffer if you put them in one.
Possible common diseases
If you own a Green Neon Tetra, it’s smart to keep an eye out for potential illnesses. These fish can be prone to ich and parasites which can lead to serious health problems.
There’s nothing special you can do when it comes to keeping them at bay other than stick to the basics. The quality of care and the condition of the tank play a large role in the likelihood of these fish becoming ill.
Water quality, low stress levels and a good diet are the most important factors to remember. If these care items are stellar, your Neon Green Tetra is much less likely to get sick.
Food and Diet
When it comes to feeding these fish, you must first have a solid understanding of their natural diet. Green neon tetras are omnivores and are used to foraging for small insects, crustaceans, zooplankton, and organic matter.
This means that you have some flexibility when establishing a diet. Many owners prefer to feed them primarily flake or freeze-dried food, which is fine. If you go this route, make sure the food is crushed or made small enough for your fish to eat. If it is not small enough, it will simply fall into the substrate and negatively affect the quality of the water.
For the sake of variation and enrichment, we recommend something like bloodworms, daphnia, or mosquito larvae. This will bring some excitement to the tank and also provide a protein rich fuel source.
Since neon green tetras are the opposite of picky eaters, it’s important to avoid overfeeding. Closely monitor the amount of food eaten when you first start feeding (or make changes to your current diet). This will tell you if you need to redial it or not.
behavior and temperament
Neon Green Tetras are fairly low maintenance as far as their temperament is concerned. These fish are quite peaceful and prefer to mind their own business and not cause any trouble in the tank.
They can get spooked when paired with more active or aggressive species (more on that below), but that’s nothing out of the ordinary for a minnow like this.
One of the most important elements of their behavior to take into account is the fact that they are schooling fish. That means they stick together in groups for safety in the wild.
Not keeping them together in your tank will cause them to live in a constant state of stress (as they think they are at risk of being eaten). This relates to the ideal size of the tank, but if you are not prepared to get at least 6 or 8 of them, it is better to choose another species of fish.
Neon Green Tetra Tank Mates
There are a number of possible tank mates for Neon Green Tetras. Because of this, it’s easier to list the criteria to look for rather than share each and every species that might work.
Ideal tankmates are non-aggressive fish of a similar size. Any aggressive species will cause too much trouble and your Neon Green Tetras will not fight back. Any fish that is too big will accidentally scare it away (or eat it by mistake).
This leaves you with a long list of possible options. If you have nothing in mind, these fish do very well in a species-only tank.
Author’s Note: In fact, we love the species-only option when it comes to Neon Green Tetras for two reasons. The first reason is obvious: it removes the need to worry about finding the perfect tank mate.
The second is one that many people don’t think about. In our opinion, these fish look best when they are the star of the show in your tank. A tank full of Neon Green Tetras swimming around in all their glowing glory is simply stunning. Having other types of fish in the tank can detract from it.
breeding tips
If you want to try to breed these fish, you will need to be patient and do everything the right way. Many experienced aquarists have failed to breed this species, so you should have reasonable expectations before attempting it.
Lowering the pH levels slightly and adjusting the water temperature so that it is on the higher side of the normal range is a good place to start. This will help replicate the water conditions in their natural habitat during mating season.
You should also reduce the amount of light entering the tank. Take stock of the amount of light you currently let into the tank and cut it in half (or even more).
Once the tank is ready to go, it’s time for you to be patient and monitor your fish. You will observe a new behavior between the male and the female (they will be close to each other and could make a lot of contact).
The female will scatter her eggs in a variety of places and the male will be nearby to make sure they are fertilized. This is an easy to spot part of the process.
When the eggs have been fertilized, you will want to remove the adult neon green tetras from the tank. They are no longer needed and this will prevent unwanted feeding incidents by adults.
Once the fish have hatched and eaten their egg sacs, it’s time for you to feed them! Brine shrimp and any other regular food source will work just fine.
Are they the species for you?
Neon Green Tetra care is incredibly rewarding. These fish are fun to watch, beautiful and sweet in their own shy way.
While they are not the most popular species in the freshwater aquarium community, this does not mean that you should not consider getting them. The reason why they are not in more tanks is a mystery to us!
If you would like more information on this species and the differences between them and their close relatives, we would be more than happy to chat with you. Our mission is to give these fish the attention they deserve!