What Do Cardinal Tetras Eat And How To Feed Them?

what do cardinal tetras eat

Are you worried about what to feed your Cardinal Tetras? If you are a first-time pet parent, feeding your glowing finned buddy is obviously a thing to stress about. However, worry, not! I am here to tell you what your Cardinal Tetras eat and how to feed your Cardinal Tetras.

Cardinal Tetras are omnivorous, so they eat meat as well as veggies. Live food like insects, larvae, fruit flies, and frozen food like bloodworms, tubifex, daphnia can be given to Cardinal Tetras. Moreover, you can give pellets and flakes to your Cardinal Tetras. Also, a vegetarian diet that consists of spirulina, chopped algae, lettuce, spinach, cucumber, and peas are good for Cardinal Tetras.

You can feed your Cardinal Tetras 2 times per day, morning and night. Only feed what your Cardinal Tetras can consume in under 2 minutes. If excess food remains at the end of 2 minutes, scoop the excess food out with a fishnet.

Another important thing is to chop and blend the food so the food can fit in Cardinal Tetras’ tiny mouth.

Image Food For Cardinal Tetra Link
Josh’s Frogs Melanogaster Fruit Fly Culture Kit (Makes 10 Cultures) buy amazon
Ocean Nutrition Instant Baby Brine Shrimp 0.7-Ounces (20 Grams) JarBrine shrimp buy amazon
1000+ Live Daphnia Magna buy amazon
Exotic Nutrition Bulk Dried Black Soldier Fly Larvae (10 lbs.) – High-Calcium Insect Treat buy amazon
9 OZ Matured Micro worm Mega Culture – Ready to Harvest – Live Fish Food buy amazon
SAN FRANCISCO BAY Brand Freeze Dried Bloodworms 1.75oz buy amazon
San Francisco Bay Brand/Sally’s Freeze-Dried Bacteria Free Tubifex – 4 oz. buy amazon
Ancestral Supplements Grass Fed Beef Heart (Desiccated) — Natural CoQ10 (180 Capsules) buy amazon
Uncle Jim’s Worm Farm 500 Count Red Wiggler Live Composting Worms buy amazon
Hikari Tropical Micro Pellets (1.58 (2 Pack)) buy amazon
Tetra PRO PlecoWafers 2.12 Ounces, Nutritionally Balanced Vegetarian Fish Food buy amazon
Tetra TetraFin Goldfish Flakes 4.52 Pound Bucket, Balanced Diet buy amazon

Best Food For Cardinal Tetras

Anyone can get bored by eating the same food every day. Therefore, you should create a balanced meal, including live food, frozen food, packaged food, and vegetable diet for your fish. Cardinal Tetras are flexible with their diet, too, so it’ll be easy for you to feed them.

You can learn about Cardinal Tetra (Paracheirodon axelrodi) – A Complete Care Guide here.

You can read below to find how you can prepare some of the food at home.

Live Food

Cardinal Tetras eat fruit fly, insect larvae, small insects, daphnia, and anything they can find to fit in their smallmouth in the wild. At home, you can give live food like brine shrimps to your fish.

Brine Shrimp

Brine Shrimps are an excellent source of protein for your adult Cardinal Tetras. Even a juvenile Cardinal Tetra loves to eat this.

First of all, you have to buy shrimp eggs from a fish store. Then, do the following to hatch the eggs.

  • Take a small tank or container and pour 2 liters of water in it.
  • Add the shrimp eggs to the tank.
  • Then, add 2 spoonfuls of kosher salt in the tank containing 2 liters of water.
  • You should maintain the temperature of the tank at 80 degrees Fahrenheit for 2 days.
  • After 2 days, the eggs will hatch.
  • Then, strain the hatched shrimps through a mesh.
  • After that, rinse the shrimp with fresh water.
  • Then, pour the required brine shrimp in the Cardinal Tetra tank for feeding.

Micro Worms

Micro worms act as a continuous source of protein because the micro worms reproduce and multiply. First of all, you should buy micro worms from a store. Then, do the following:

  • Use a shoebox or any other box similar to a shoebox. A plastic container is ideal.
  • In the middle of the box, spread some oatmeal.
  • Then, add some brewer’s yeast to the top of the oatmeal.
  • After that, add the micro worms to the box and wait for a few days.
  • What happens in a few days is that micro worms start feeding on the oatmeal and start a life in the box. There will be the addition of new micro worms in the box.
  • If you want the micro worms, pick up the ones on the side, and feed it to your fish.

Frozen Food

Frozen food like tubifex, bloodworm, and any protein is good for Cardinal Tetras as there is less chance of infection. However, frozen food has fewer nutrients than live food. Let us learn how to make frozen food.

Frozen Beef Heart

You can buy beef from any cold food store; it doesn’t have to be a fish store.

Then, chop up the beef into tiny pieces. It is even better to blend the beef. After that, keep the blended beef in your freezer.

Whenever it is time to feed your fish, take out the frozen beef from the freezer. Then, cut a tiny piece and let it rest for some time. After the beef melts a little, feed it to your Cardinal Tetras.

Any Other Meat

Any other protein like chicken, fish, lamb, and so on can be fed to your Cardinal Tetras. You can even add earthworms to their diet.

However, you should make sure that the protein should be cut into tiny pieces so your finned buddy can eat with ease.

Commercial Packaged Food

Packaged food like pellets, wafers, and flakes are developed by scientists and fish experts. These people have dedicated their effort to creating food that is packed with nutrients. Thus, I think that packaged food suits the best for your Cardinal Tetras.

You should buy a high-quality flake food (free from fillers) that suits best for Tetras. Moreover, you should purchase food containing protein, fibers, and omega fatty acids. You should avoid wheat, barley, soy, and gluten in the packaged food.

Learn more about ‘How To Feed Tetra Fish Fry Properly | Dos and Don’ts With Alternative Fry Food.’

Some commercial food has tubifex and bloodworms, which your Cardinal Tetra will love. Some even have color enhancers to help your Tetra glow brightly in the tank!

Related article: Albino Glowlight Tetra – Everything You Need To Know About

I understand that some quality flakes might cost you a bit more compared to normal fish food. But, trust me, the price is worth it. And there is less chance of infection too.

Cardinal Tetras are mid-level swimmers, and they only eat floating food. Anything that has sunk below in the tank is out of your finned buddy’s interest. Thus, you can search for floating pellets, wafers which will float in the tank.

The following are some commercial food:

Vegetable Diet

Cardinal Tetras are omnivorous and don’t mind eating vegetable matter. You can occasionally add vegetables to their meat diet to create variation.

You can cut vegetables like spinach, spirulina, cucumber, lettuce, peas into tiny bite-size pieces. Blending the vegetables also makes it easier for your Cardinal Tetras to eat.

Sometimes, algae grow inside the tank, which is also a good option for your Tetras to feed on.

A Feeding Guide For Cardinal Tetras

Now that you know what your Cardinal Tetra eats, you should also know how often and how much to feed your finned buddy.

How Often To Feed Your Cardinal Tetras In A Day?

If you categorize your eating time with the feeding time for your Cardinal Tetras, then you won’t forget to feed your fish.

As overfeeding can be a problem, less is better for Cardinal Tetras.

You should feed your finned buddy at least 2 times a day. However, if you feed frequently, smaller feedings are preferred.

Also, you should also make sure to spread out the feeding time for your fish. This means that you should feed your fish early morning and then late at night. If you feed your fish too early, then your fish might not eat the food.

Most importantly, always feed your fish on time.

How Much Food Should You Give?

Cardinal Tetras are small fish with smallmouth. However, Cardinal Tetras are schooling fish and live in a group of 10 or more. So, you should calculate the food according to the number of Cardinal Tetras.

Are Tetras Schooling Fish? – Easy Schooling Fish. Find out here.

During the feeding time, put a small amount of food for your Cardinal Tetras in the tank. If your Tetras can finish the food you gave in about 2 minutes, then that amount of food should be provided to your fish at each feeding.

However, if your fish doesn’t finish the food at 2 minutes, then that excess food should be removed with a fishnet.

If your fish finishes the food very quickly, under 2 minutes, then add more food until the 2-minute mark.

Feed only what your Cardinal Tetras can consume under 2 minutes.

What Will Happen If You Overfeed Your Cardinal Tetras?

While feeding your fish, your fish might swim on the top, looking like they want more food. And you might believe that, indeed, your lovely buddy might be hungry. In the end, you might end up feeding 5 spoonfuls of pellets to your fish. However, this is a huge mistake you’re making.

  • Overfeeding in your fish can cause bloating, which causes several diseases.
  • Moreover, wasted food and excess fish wastes create a poisonous environment in your tank. The wasted food decomposes and creates ammonia. The spiking ammonia level creates an imbalance of water parameters. Ultimately, your fish will get diseases as ammonia is poison to your fish.
  • Cloudy water develops in the tank, which is a result of decomposed food. This requires you to clean the tank frequently.

Frequently Asked Questions

Can You Prepare The Food For Cardinal Tetras At Home?

Yes, as I have described above, your Cardinal Tetras can appreciate your cooking. Moreover, you can save up a lot on making home-made food.

But, there are some downsides to homemade food as well. Homemade food should be prepared hygienically. All the parasites should be removed from the meat.

If your fish eats parasites in the meat, then your fish suffers from diseases.

I have written an article on Tetra Fish Diseases and Treatments. Check it out!

How Much Do Cardinal Tetras Eat?

In the wild, Cardinal Tetras are opportunistic feeders. This fish eats as much as they can eat at any chance they get. This is because the fish doesn’t know when it will get its next meal.

That is why you mustn’t give your Cardinal Tetra too much food. Because Cardinal Tetra can eat until their stomach bloats.

If you understand this, you will give the required amount of food for your Cardinal Tetras.

How Long Can Cardinal Tetras Go Without Eating?

Like any other Tetra fish, a Cardinal Tetra can go 7 days without food. Their scavenger instinct makes them live without food for such a long time.

Most fish owners fast their Cardinal Tetra once a week to clear their digestive system. And you can also diet your Tetras once a week.


I hope you understood what you should feed to your fish. You also got information on the preparation of homemade food so your fish can appreciate your cooking.

All in all, Cardinal Tetras are not fussy eaters. Overfeeding can be a problem, though. However, if you have read this article, you will have no problem feeding your lovely fish. Happy feeding!

Related article:

  1. Neon And Cardinal Tetra Tank Mates – Compatible Tank Mates
  2. Neon v/s Cardinal Tetra – The Difference
  3. Best Tank Size For Tetra Fish? Neon, Cardinal, and Other Similar Tetras

Leave a Comment

Your email address will not be published. Required fields are marked *

Scroll to Top