How To Keep Cardinal Tetras Happy?

When you own a pet, its happiness and health are some of the most pioneer concerns you have. Cardinal tetras are beautiful fish, but they are also sensitive. So, if you plan to keep Cardinal tetras, you must be similar to all the ways that make them happy. Don’t you want a happy pet? If you do then, read on to find the methods that can keep your Cardinal tetras happy.

To make sure your cardinal tetras stay happy and healthy, you need to provide them with an environment that simulates their natural habitat as closely as possible. For example, the cardinal tetras are from the Amazon River. They require water with a high pH level, less than 15 dGH but more than five dGH hardness, and temperature between 24-27 degrees Celsius.

Besides these, there are many other things that you need to consider if you want to keep your Cardinal tetras happy. So, here in this post, we will go through each in detail. We hope it will help you.

Are Cardinal Tetras Happy Pet?

Cardinal Tetras are one of the most colorful fish available as pets. They make fantastic additions to any home aquarium with striking red and blue fins. In addition, these pets are not aggressive and can adapt well to various water conditions, making them ideal for novice fishkeepers.

Cardinal tetras are undoubtedly one of the best freshwater fishes for community tanks. They are active fishes that love to swim in the middle sections of an aquarium. Moreover, they are easy to care for. So, you won’t have any problems associated with these fishes.

If you notice them carefully, they will mostly enjoy the place they live in. But, for this, there are certain things that you need to make sure of.

So, how do you keep your Cardinal tetras happy and healthy? Don’t worry. We have answered it below.

How To Keep Cardinal Tetras?

Do you have Cardinal tetras, and are you struggling to find the correct ways to make them happy?

It is not very difficult to make them happy as they are calm, peaceful, and friendly. Cardinal tetras don’t show any aggression or anger against other fish kept with them. You can easily manage to maintain their tank by following a few simple steps below:

Keep Your Cardinal Tetras At Optimum Water Temperature

The cardinal tetras thrive in a temperature range of 73 to 81 degrees Fahrenheit. If the water temperature is too low, they will become lethargic and not eat. If it is too high, they may suffer from heat stress and die.

Monitor The pH Level

The preferred pH range for cardinal tetras is between neutral and acidic. Because of their origin in the Amazon River and its tributaries, the pH level fluctuates between neutral to acidic water.

Monitor The Water Quality

You need to maintain high water quality to keep cardinal tetras happy and healthy. Therefore, you should look out for three main parameters when monitoring your aquarium water quality. These are pH, ammonia, and nitrite levels.

Provide Enough Light

Cardinal tetras need a bright environment to live in. They will become stressed if they do not have enough light. Therefore, you should provide at least eight hours of light per day to your aquarium.

Feed Them A Varied Diet

The cardinal tetras are omnivorous fish and require a varied diet to stay healthy. Make sure you provide them with food items like pellets, flakes, frozen foods, and live foods.

Make Sure You Have A Suitable Number Of Cardinal Tetras

One cardinal tetra requires at least five gallons of water to stay happy and healthy. You should never keep more than ten cardinals in your aquarium as they will become stressed due to the lack of space.

Provide Plenty Of Plants And Hiding Places

Cardinal tetras are schooling fish, and they like to live in groups. They feel safe and secure when they have plenty of plants and hiding places in their tank. It will also help to reduce stress levels.

Cardinal tetras are very easy to care for in an aquarium environment. If you keep their water clean by performing regular partial water changes and feeding them a varied diet, they will be healthy and happy.

What Problems Might You Face When You Keep Cardinal Tetras?

When you keep cardinal tetras, you might face a few problems. The first is to keep them in a school of five or more. If you keep them by themselves, there may be an aggression issue, and cannibalism will occur between the cardinal tetras.

Besides this, they need good water quality and a stable temperature to be happy. Although Cardinal tetras are hardy, they are tropical fish. It means that you should keep their aquarium near a heater or in an area of your home where the temperature won’t fluctuate too much, such as by a window looking out to an indoor garden kept warm by sunlight.

When it comes to keeping cardinal tetras happy with other types of fish, then there may be issues with aggression towards them. For example, when you keep many fishes too big for the tank, they may eat smaller cardinal tetras.

What Do You Need To Keep Cardinal Tetras Happy?

Keeping cardinal tetra happy requires a few things. They are:

  • A tank that is at least 15 gallons
  • Place decorations like driftwood, live plants, and rocks. Remember to use plastic or silk plants as these fish will chew on real ones, harming them! If you’re keeping cardinal tetra with other types of tropicals, then make sure they are all compatible – for and rocks.
  • A filter
  • Heater to keep the temperature stable in your aquarium
  • An area with a warm temperature for your cardinal tetras. If you can’t provide this, then it’s better not to have them at all.
  • A diet of mostly flake food with some live and frozen foods

What to Avoid When Keeping Cardinal Tetras

When you’re keeping cardinal tetra, there are a few things you should avoid.

One is overfeeding them, which can lead to pollution in the tank and health problems for your fish. Another is using tap water to fill your tank, as the chlorine and other chemicals in it can harm them. Make sure you get some of this tap water before adding it to your aquarium so that they are safe for fish.

Finally, don’t forget to keep up with cleaning. While this is tiresome work, it is vital to want happy cardinal tetras who will stay around and breed.

Some FAQs

How Long Do Cardinal Tetras Live?

Cardinal tetras live for about four to five years. As it is relatively short,  you should work to keep them happy during that time.

What Is The Best Diet For Cardinal Tetras?

Many people feed their cardinal tetra regular fish food, but they also love frozen brine shrimp. You can buy it at your local pet store or online and provide them a few times a week for some extra protein in their diet.

How Often Should You Feed Them?

Cardinal tetras are omnivorous, so that they can eat a variety of things. It would be best to feed them once a day, but you can vary the amount depending on eating. For example, you don’t need to give them much if they’re getting their food from the tank. But if you’re feeding them frozen brine shrimp or other treats, then give them more.

Can You Put Other Fish in with Cardinal Tetras?

Many fishes can live happily with cardinal tetra. Some examples are neon tetras, rummy nose tetras, and glowlight tetras. Just make sure to research the specific species before adding them because some will thrive while others won’t do well.


Overall, Cardinal tetras are beautiful fish that can make a great addition to any aquarium. However, these fish are happiest when they have a healthy and comfortable environment, so it’s essential to take care of them properly.

You can keep cardinal tetras happy by providing them with a healthy and comfortable environment. For example, ensure the tank is clean, provide plenty of plants and decorations, and give them enough food. With these simple tips, your cardinal tetras will be thriving in no time!

Tips and Warnings: It’s a good idea to acclimate cardinal tetras slowly when you first put them in your tank. It helps prevent the fish from feeling stressed out, making it harder for them to stay healthy. Also, ensure that they have enough space by providing their aquarium is 30 gallons or more.

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