Cardinal Tetras Size: Everything You Wish To Know

Cardinal Tetras are beautiful fish that can add some flair to your aquarium. They come in many different colors and sizes, but there is one question that all Cardinal Tetra owners want to know: “How big do Cardinal Tetras get?” So what is the size of Cardinal tetras?

Cardinal Tetra is a medium-sized fish that grow up to be about four inches in length. They come from South American rivers and streams, but they thrive in many different water conditions. Cardinal Tetra fish don’t need much space, but you should provide them with an aquarium of at least five gallons if you plan to keep them.

In this post, we will answer the question of Cardinal Tetra size by listing their average length and weight and giving you an idea of what kind of tank they require based on their size.

What Is Cardinal Tetras?

Cardinal Tetras is a species of tropical fish that belongs to the Characidae family. They are present in South America and typically inhabit slow-moving streams, rivers, floodplains, and swamps.

Cardinal tetra fish are peaceful, non-aggressive schooling fishes that will look great in any tank setup. Therefore make great fish for community tanks. Although Cardinal tetras are relatively small fish, they grow up to an approximate size of ¾ inches. Their care is very similar for most schooling species and, therefore, easy to maintain in the aquarium setting.

Cardinal tetras require water with a slightly acidic pH level of 4.6-6.2 and a temperature within the range of 71-80 degrees F. In addition, the water of the tank must have a GH (general hardness) level of around 150-200 ppm and a KH (carbonate hardness) of 100-150ppm.

Cardinal Tetras Size

Cardinal tetras are a prevalent fish to have in the home aquarium. Their size can vary from three-eighths of an inch to one and a half inches, but most people keep them around four inches.

In the wild, Cardinal tetras are present in the Amazon River basin. Cardinal Tetras’ coloration makes them so popular. They have a deep red body with black stripes. Cardinal Tetras like to be in the school of five or more fish and will do best when kept around plants and other fish that aren’t too big.

Male cardinalfish are usually more significant than a female of the same species. Frequently, though not always, females have a deeper body shape and a more rounded forehead compared to males. Also, their tails tend to be shorter in comparison with male Cardinal Tetras.

Cardinal tetras grow up to three inches in length. Therefore, they require at least around 30 gallons of the tank. But if you want to keep a more extensive number of Cardinal tetras, it is best to use a bigger tank.

What Are Different Species Of Cardinal Tetras And Their Size?

There are four different species of cardinalfish that you can buy from the market. They include – Neon, Congo, Sunset, and Golden. The size of each type varies as per their names.

Neon Cardinal Tetras And Their Size

Neon Cardinal Tetras are the smallest of all four types. These cardinals can grow up to an inch long, which is why they need a tiny piece of water in their tank. They are beautiful fish with a red stripe running from the gills to the tail. These Cardinal Tetras look extremely attractive and vibrant in a group of six or more fish.

Neon Cardinal Tetras need small tanks with lightly planted areas to take cover if required, as these cardinals are not very aggressive by nature and will be fine even in crowded aquariums.

Congo Cardinal Tetras And Their Size

The Congo Cardinal Tetras are a bit aggressive and need to be in groups. They grow up to about one and a half inches long, which is why they need at least 29 gallons of water in their tank. These Cardinal Tetras are peaceful towards other cardinal species but can be aggressive towards their kind.

Sunset Cardinal Tetras And Their Size

The Sunset Cardinal Tetra is the largest among all four types that you will find readily available in the market. These Cardinal Tetras grow up to two inches long and need at least 30 gallons of water in their tank.

They are peaceful towards other cardinal species but can be aggressive with their kind if there is not enough space to live happily.

Golden Cardinal Tetra And Their Size

The Golden Cardinal Tetra is also a peaceful Cardinal Tetra that grows up to one and half-inch long. It needs at least 20 gallons of water in its tank.

They are incredibly colorful with yellowfins, making them look gorgeous when you keep them in small groups of four or more fish.

How To Increase The Size Of Cardinal Tetras?

Cardinal Tetras are tiny fish. These fish is the smallest species of aquarium fish in Central America. Cardinal tetra ranges from one to three inches long, making them an ideal choice for nano tanks up to ten gallons or so. However, some of the ways to increase the size of Cardinal tetras are:

Feed Cardinal Tetras Right Food In Right Amount

Cardinal tetra requires a lot of attention when it comes to their feeding. They are real-time eaters, and they will start eating the food in your hands if you keep them near enough.

It would be best to feed Cardinal tetras with a high-quality flake or mini pellet foods that include plant matter and animal protein, such as bloodworms. It is best to provide them at least twice a day in small quantities, so keep that in mind when setting up your aquarium for them. Owners most often feed Cardinal tetras frozen or freeze-dried bloodworms, tubifex worms, and brine shrimp.

Increase Cardinal Tetras’ Feeding Frequency

Cardinal Tetra is a small fish. Therefore, you need to feed them at least twice daily to keep them happy and active. Many experts recommend feeding cardinal tetra fish once a day. But if you are keeping Cardinal tetras in schools of five or more, it is much better to feed them twice a day.

Provide Cardinal Tetra Fish With Tank Companion

Cardinal tetra fish like to live with other cardinal tetra fish as it makes them comfortable and saves your effort for keeping an eye on every Cardinal Tetra in your aquarium. Some of the tankmates best for Cardinal tetras are Endler’s Livebearer, Dwarf Gourami, Harlequin Rasbora, Neon Tetra, Cardinal tetras, and many more.

Keep Cardinal Tetras Tank Clean

Cardinal tetra fish prefer to live in a clean environment. Therefore, you should keep their tank and all accessories very clean and bacteria-free at any cost. Use water conditioners before introducing them into the new tank or re-cycle program for used tanks.

Provide Cardinal Tetra Fish With Natural Habitat

If you want your Cardinal tetras to overgrow and stay healthy, then provide them with natural habitat. This means that if you house these fish in an aquarium environment, it is best to add some live plant matter such as java moss or Anubias nana.

The live plants will give some space for Cardinal Tetra fish to hide among when they feel threatened.

Do not overstock Cardinal Tetras’ Tank.

Cardinal tetra fish are brilliant in that they can sense their surroundings. Therefore, when there is a large amount of space to roam around in the water, Cardinal Tetra will be more active and happier than ever before. So if you want your Cardinal tetra fishes to grow quickly, avoid overcrowding Cardinal tetra fish in an aquarium.

Maintain Cardinal Tetras’ Tank Temperature

Cardinal tetra fish like to live at room temperature (around 72-80 degrees Fahrenheit). They will do much better if you keep them within this range. They are susceptible to water quality, so maintaining their water temperature is of the utmost importance.

Cardinal tetra fish may die if you keep their tank temperature above 80 degrees Fahrenheit and below 60 degrees Fahrenheit for an extended period. So make sure that your aquarium has a functional heater at all times.

Provide Cardinal Tetras With Suitable Tank

Cardinal tetra fish like to live in small schools, so make sure that you provide them with a tank of at least ten gallons. These fish do not like bright lights or loud noises. So they will thrive much better if the light cycle is of only about twelve hours per day and no air pumps are running on your Cardinal Tetras’ aquarium.

Cardinal Tetra care is pretty simple, so if you follow these tank recommendations, then your fish will thrive beautifully.

Some FAQs

What Is The Normal Size Of Cardinal Tetras?

The standard size of Cardinal Tetras is around three inches. You can easily find them in pet stores and they come in a variety of colors such as red, orange, gold, or silver. The cardinal tetra has an average lifespan of about five years, and they are effortless to care for.

What Is The Smallest Species Of Cardinal Tetras?

The smallest species of Cardinal Tetras is the Neon Cardinal tetra, which can grow up to about one inch long. They are a bright neon orange with a small black line going down their body, and they have an average lifespan between three and four years.

What Is The Largest Species Of Cardinal Tetras?

The largest Cardinal tetra is the one that can grow up to about four inches long. They vary in color from a bright red with a small black stripe going down their body to a silver-blue coloration depending on who you ask and where they live. Cardinal Tetras have an average lifespan of five years as well.

Does The Size Of Cardinal Tetras Affect Their Lifespan?

Cardinal Tetras usually have a lifespan of up to five years. Although some aquarists believe it, there is no evidence supporting the fact that Cardinal Tetras with larger sizes live longer.

However, it is best to keep Cardinal tetras in groups of at least six fish so that the years they live are happier.


Cardinal tetras are great fish for beginner and experienced aquarists alike. They are hardy and peaceful minor characters. So, they can live in a wide variety of community tanks with other peaceful species such as guppies and mollies. Cardinal tetra care is not too difficult, and they seem to be a favorite among aquarists.

Cardinal tetras are everything you wish to know about this exciting fish species, which will make an excellent addition to your tank. Hopefully, this post gave you all the information you need to know about Cardinal Tetras Size.

Scroll to Top