How Do You Feed Cardinal Tetras? A Guide for Beginners

Cardinal tetra is the most popular freshwater fish in North America. It’s a beautiful, vibrant red and white fish that many people enjoy keeping as pets. Of course, most aquarists want to keep this stunning creature in their aquarium. But before that, how to feed Cardinal tetras is an important question that you need to know.

Cardinal tetras are not so difficult to feed. Being omnivorous fish, they can eat both plant and animal-based food. You can provide them with flakes, frozen food, or live prey.

Remember that the cardinal tetra is a small fish, and you have to control its diet so it doesn’t get overweight quickly. Cardinal tetras are not picky eaters but try to vary their menu with different types of foods.

If you are a beginner, you might have any questions regarding this fish. Hopefully, you will find all your answers below.

What Type Of Fish Is Cardinal Tetra?

Cardinal tetra is a small freshwater fish belonging to the Characidae family. They are native to South America and can be present in rivers and streams of Brazil, Columbia, Ecuador, and Peru.

Cardinal Tetras range in color from bright red with black markings on their fins to silver-white with red accents. These fish generally grow up to one and a half inches long. They are peaceful fish that you can keep in small schools of about six to eight fish.

Diet Of Cardinal Tetras

Cardinal Tetras should eat a variety of foods, and there are some staple choices that you can offer to them. Most of these species are omnivorous and need a balanced diet.

Cardinal tetras need a variety of foods to stay healthy. Such as brine shrimp, bloodworms, small worms or insects (flying around the tank), tubifex worms, daphnia (water fleas), infusoria (microorganisms found in water), and also commercial flake food for them to eat.

Cardinal tetras also need some plant matter in their diet, so it would be good to include some flaked foods with plant matter in the food mix. You can even give them some veggies like cucumber, zucchini, and peas. Just remember to cut these vegetables into small pieces.

How To Feed Cardinal Tetras?

Cardinal Tetras are a popular fish species and for a good reason. Their care is relatively straightforward in comparison to other types of freshwater aquarium fish. They usually don’t require special lighting or filtration system in the tank.

Besides this, these fish are straightforward to feed and aren’t picky eaters. In addition, Cardinal tetras are omnivorous that means they can eat both plant and animal-based diet. So, there are a variety of options available for them.

However, you must make sure that you do not overfeed Cardinal Tetra. Their care requires that you feed them only about twice a day in small quantities to prevent overfeeding and the resulting malnutrition, leading to disease or even death.

So when it comes to Cardinal Tetra feeding habits, it is best not to change their food too much at once since they are susceptible fish that quickly feel stressed.

What Cardinal Tetras Eat?

In the wild, Cardinal tetra fish eat small invertebrates such as worms and insects along with plant matter like algae and leaves from plants in their habitat.YYouanced diet of tropical fish flakes and small bites such as brine shrimp or bloodworm in an aquarium environment.

What Should I Feed My Card in an aquarium environmental Tetras?

Cardinal Tetras prefer to feed on living food. They enjoy bloodworms, brine shrimp, and daphnia most of all. If you cannot provide them with live foods, you can even use freeze-dried foods as alternatives. Frozen foods will probably work best for your fish if they are available to you.

However, some plants and animal-based food that you can feed to tetras are as follows.

Plants-Based Food To Feed Cardinal Tetras

Plants and veggies are a rich source of minerals for Cardinal tetra. So, some of your options are:

  • Spinach
  • Squash
  • Zucchini
  • Carrots
  • Leafy greens, such as collard
  • Romaine lettuce
  • Alfalfa sprouts
  • Grains

Animal Food To Feed Cardinal Tetras

Animal-based foods are a source of protein for Cardinal tetra. They will help in the growth and development of these fish. These foods are:

  • Bloodworms (frozen or freeze-dried)
  • Brine shrimp (frozen or freeze-dried)
  • Tubifex worms (live, frozen, or freeze-dried)
  • Mosquito larvae (freshwater)
  • Earthworms (canned and live)

How Much Should I Feed Cardinal Tetras?

Cardinal tetra fish are omnivorous and shoaling freshwater species, so they usually eat plant matter and small invertebrates such as crustaceans and worms.

When you go to feed your fish, the first thing that you want to do is check how much they are eating. Cardinal Tetras should be fed very little at a time, but you also don’t want them to overeat that the stomach expands and makes their abdomen look bloated. If this happens, stop feeding your Cardinal Tetra for two days until the fish is again in shape.

How Often Should I Feed Cardinal Tetras?

It would be best if you fed Cardinal tetras at least once or twice per day, but the frequency depends on the number of fish in your aquarium and their size. These fish are peaceful and can live happily with other non-aggressive species of fish without any problems. For example, cardinal tetras do well when you pair them with danios, platies, harlequin rasbora, black neon tetras, and other fish that do not nip or harass them.

How To Know Cardinal Tetras Are Eating Enough?

Cardinal tetra will eat anything you put in the tank. They are generally not that picky when it comes to food, but there is a big difference between what they naturally eat.

Some of the signs that Cardinal tetras are eating enough are:

  • Cardinal Tetras are still looking for food in the tank.
  • You can see them swimming toward your hand if you put it close to them.
  • Their bellies will be complete and round.
  • All Cardinal tetras have a white or cream-colored stomach.
  • They do not show unusual behaviors like fin-nipping, hiding, or not eating.

Some Tips To Follow When You Feed Cardinal Tetras:

Cardinal tetras love eating and will happily much upon anything you offer them. So, you must follow tips when you feed these fish:

  • Always make sure that the food is not big enough and fits in their mouth. Otherwise, your fish might choke and die.
  • Also, feed them with small fish pellets and flakes because they are easier to eat than the large ones. Cardinal tetra can also get sick if you give them irregular food such as algae wafers or bloodworms. So, make sure that it is part of their daily diet.
  • You should know when you should feed Cardinal Tetras and when not to. For example, these fish can feel irritated if you provide them with food when they sleep, so you shouldn’t do this.
  • You must also know how much Cardinal tetra fish eat daily to maintain a healthy lifestyle for these fishes since overfeeding is one of the Cardinal tetra problems.
  • Last but not least, you must always clean the fishbowl and replace water regularly to maintain good hygiene for Cardinal Tetras because this will also minimize the chances of diseases from occurring in them.

Some FAQs

Do Cardinal Tetras Eat Their Babies?

Cardinal Tetras are not cannibals. Usually, the babies will be safe even if they are in the same tank as their parents. Although it is less often, sometimes overcrowding and pollution might disturb your fish. 

As a result, cardinal tetra will eat their babies due to anxiety and stress.

Do Cardinal Tetra Eat Other Cardinal Tetra?

Cardinal tetras are small, and their babies are even smaller. So, these fish do not think of the babies as food. But if they are starving and lacks enough food in their tank, they might sometimes thrive on others’ babies.

Do Cardinal Tetras Eat Bacteria?

Cardinal tetra will eat bacteria while they are grazing on algae. However, it is not their primary source of nutrients, so do not worry about them overeating awful stuff and getting sick from it. On the contrary, it is good for the health of Cardinal Tetras and Cardinal Tetra Babies to have tiny algae in their diet.


Continuing with Cardinal Tetras, there is no need to be concerned if you see one of them eating the other Cardinal’s scales. This doesn’t hurt either fish, and they will always grow back within a couple of weeks. These fish are straightforward to care for, and any beginner should have an enjoyable time keeping these beautiful fish in their tank.

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