Will Cardinal Tetras Eat Planaria? The Diet For These Prey Fish

Cardinal Tetras are a colorful fish native to the Amazon. Cardinal tetra care can be easy as long as you provide them with their needs and keep an eye on tank conditions, but one thing that people wonder about is if cardinal tetras eat planaria or not?

The diet for these prey fish are usually live feeders. Live food commonly used are bloodworms, daphnia, brine shrimp, and mosquito larvae. Thus, it is not unusual for Cardinal tetras to eat planaria. In addition, Cardinal tetras are omnivorous fish, meaning they eat plants and animals.

If you are new to fish keeping, you may have many questions. They are mostly related to the diet, tank, and feeding schedule of Cardinal tetras. In this post, we will discuss the Cardinal tetra diet and Cardinal Tetras eating planaria.

What Is The Best Diet For Cardinal Tetras?

Cardinal tetras are a hardy species of fish that can eat just about anything. This fish will often do well on flake or freeze-dried foods, especially if you mix in live food like worms and insects to their diet every once in a while.

Cardinal tetras are omnivorous and eat both plants and animals. They have a diet consisting of insects, worms, algae, crustaceans, and plant matter in the wild, similar to what they eat in captivity as pets.

Cardinal tetras are not picky about their food in an aquarium environment. But many owners say that if they get more comfortable with hand feeding. Then they will prefer only hand-fed meals.

Some Cardinal tetras can eat just about anything from flakes for carnivores, freeze-dried tubifex worms, and bloodworms, as well as small feeder fish like guppies or even a ghost shrimp if it is hungry enough.

Along with protein source, you must also include some vegetables in their diet. Cardinal tetras can be fed zucchini, spinach leaves, cucumber, and other veggies. Cardinal tetras thrive on a varied diet that includes both plant and animal matter in the wild and during their lifetime, whether you keep them captive or not.

Will Cardinal Tetras Eat Planaria?

Cardinal Tetras will eat Planaria. Cardinal Tetras like eating smaller fish, crustaceans, and invertebrates like planaria. So if you want to feed your Cardinal tetra, other foods, make sure they are small enough particles. It is because the Cardinal tetras have a more petite mouth compared to its body size.

Cardinal Tetras are tiny fish that will eat smaller prey. Cardinal tetra is a predator and eats other invertebrates like the planaria because it is in their nature to do so. Usually, their diet includes crustaceans, small fishes, worms (like bloodworms), insect larvae, brine shrimp eggs/nauplii, and even smaller Cardinal Tetras.

Cardinal tetra is a fun fish to keep because it will eat other invertebrates like the planaria, but make sure you buy them big enough Cardinal tetras to fit in their mouths.

Is It Ok To Give Planaria To Cardinal Tetras?

Yes! Cardinal tetra fish might have a hard time eating these worms, but they will eat planaria. These fish can gain weight from planarian worms, and these foods are a good source of protein for Cardinal Tetras if they eat them.

Cardinal Tetras are small, freshwater fish. Cardinal tetra’s diet consists of vegetable matter and insects in the wild. Generally, they will eat anything that fits into their mouth. Including planaria in the diet of Cardinal tetras will not hurt them, but Cardinal tetra fish might have a hard time eating these worms.

Pros Of Planaria In The Diet Of Cardinal Tetras:

Some of the benefits of including planaria in the diet of Cardinal Tetras are:

Planaria Are Protein Source For Cardinal Tetras

Cardinal Tetra fish are a predatory species that need protein in their diet. Therefore, planaria can be a great source of protein for Cardinal tetras if they will eat them.

Planaria Are A Good Source Of Vitamin C For Cardinal Tetras

Cardinal tetras obtain vitamin C from planarian worms, which is necessary for them. These fish will need to absorb vitamin c from their diet for them to maintain healthy gill function. Cardinal tetras can increase the chances of survival by including planaria in their diets if they are deficient in Vitamin C.

Planaria Are Great For Gaining Weight

Cardinal Tetras need to gain weight, and planarian worms can be an excellent way for them to do so. These fish are an omnivorous species that need protein in their diet. Cardinal tetras can gain weight from planarian worms. It is because planaria are an excellent source of protein for Cardinal Tetras.

Cons Of Planaria In The Diet Of Cardinal Tetras

Some of the cons of including planaria in the diet of Cardinal Tetras are:

Cardinal Tetra Fish Might Not Eat Planaria

Cardinal tetra fish are very picky eaters. Therefore, they might not be willing to eat planarian worms, leading to a Cardinal tetras malnourishment or death.

Planaria Are Hard To Digest For Cardinal Tetras

Cardinal tetra fish have small stomachs, and it can be challenging for Cardinal tetra fish to digest planaria. If Cardinal Tetras do not eat these worms, they might cause digestive problems or make Cardinal Tra sick. Cardinal Tetra fish might also die from eating planaria if Cardinal tetras do not eat these worms.

Planaria Cannot Be The Sole Diet For Cardinal Tetras.

Despite the nutritious value of planaria, they singly cannot fulfill all the nutritional requirements of Cardinal tetras. Therefore, you should feed cardinal Tetra fish a variety of foods for their proper growth and development.

How Much Planariia Should I Feed Cardinal Tetras?

Cardinal Tetras are always hungry, so you must feed them as much as they need. They will eat planaria until there is no more food for them in the aquarium tank or bowl.

Many fish keepers reported that Cardinal tetras would eat all of the available Planariia within an hour. So, it would be best if you fed Cardinal tetras with enough Planariia until they were complete.

Cardinal tetras will not stop eating planaria until their stomachs become too big. Or they become unable to swim correctly because of their bulging belly. So, it would help if you fed Cardinal tetras with enough Planariia until they were complete.

How Often Should I Feed Cardinal Tetras?

Cardinal Tetra fish will eat planaria every day, so you should feed them every day as well. These fish have a very high metabolism rate, and you must provide Cardinal tetras at least twice a day to keep them healthy.

Cardinal Tetras are a prevalent type of fish, and they can grow to be between six and eight inches in length. However, Cardinal tetras eat planaria at least one inch long, so you should make sure your Cardinal Tetra tank has plenty of food for them every day.

How Do You Feed Cardinal Tetra Fish?

Cardinal Tetras are an omnivorous species of fish. They have teeth on their jaws and the palate, which means they can be both carnivores and herbivores. The main diet for Cardinal tetra involves a combination of plant matter and bloodworms or brine shrimp.

However, some tips that you must follow when you feed Cardinal tetras are:

  • Do not feed Cardinal Tetras with bloodworms or brine shrimp every day as it can make them sick. You should only do this about once a week and mix these two foods to ensure they get their required amount of protein.
  • Also, be careful when you buy Cardinal Tetra food because some pet shops will sell fish food sitting in their store for a long time, and it hasn’t gone well. You can also feed Cardinal tetras with frozen foods like brine shrimp, bloodworms, and daphnia to give them the protein they need without any added chemicals or preservatives that could hurt them.
  • Be sure not to overfeed your Cardinal Tetra Fish as it is awful for them and can lead to an early death. However, Cardinal Tetras will eat up to fifty percent of their body weight in food every day, so if you keep this in mind when adding Cardinal Tetra fish flakes or pellets into the tank, it should be fine.
  • And lastly, remember that Cardinal Tetras, like all other species of tropical fish, need to be fed at least three times a day. Cardinal Tetras do not have stomachs and can quickly get sick if you forget to feed them, so make sure that the food does not sink into their tank for too long as it will become rotten and polluted very quickly.


Summing up, Cardinal tetras can eat planaria if Cardinal tetras are willing to do so. Still, these worms might not agree with Cardinal Tetra’s digestive system, and they cannot make up the only diet for Cardinal Tetras. Therefore, the best way to feed planaria is an occasional treat for Cardinal Tetras that will not cause any harm to Cardinal tetras.

Thanks so much for checking out this post! I hope you learned a lot from it, and if you have any further questions about Cardinal Tetras and Planaria, please ask them in the comments! I will be more than happy to answer.

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