Tetra Fish

The Ultimate Tetra Care Guide for Beginners

Aquarists, both beginner and experienced, know the importance of having tetra fish in their tanks.

These hardy aquarium fish come in beautiful colors and can add excitement to any tank set-up.

But before you rush out to buy some neon tetras, it’s important to learn about their care requirements.

This guide will teach you everything you need to know about keeping your tetras healthy and happy.

Origin of Tetra Fish

Neon tetras are native to the clear water and blackwater streams and tributaries in Brazil, Columbia, and Peru’s Orinoco and Amazon river basins.

These are regions of dense jungle canopy where little light reaches the water.

Tetras prefer to live in shoals that reside predominantly in the middle layer of the water.

They are typically all captive-bred, with the majority coming from Asia and Eastern Europe.

Several captive-bred types have recently become available, including the long-finned neon tetra and a golden strain that is essentially a semi-albino variety, as well as a diamond neon tetra that appears to be sprinkled with metallic scales along the top portion of its body.

Types of Tetra Fish

Believe it or not, there are over 150 different species of tetra fish, but they all belong to three main families:

The Characidae: The Characidae, also known as the characins or characids, are a family of freshwater subtropical and tropical fish that belong to the order Characiformes.

This family contains the most popular tetras, such as the Neon Tetra and the Cardinal Tetra.

The Alestidae: The African tetras (family Alestidae, previously known as Alestiidae) are a species of characiform fish that is only found in Africa.

This family has about 18 genera and 119 species. The Congo tetra and African tigerfish are two prominent examples.

Lebiasinidae: The pencil fish is a species of freshwater fish that lives in Central America, Panama, and South America.

They are often tiny and are frequently utilized as ornamental fish in aquariums, including popular animals like the pencilfish and splashing tetra.

As we mentioned, there are over 150 species of tetras, we can’t possibly list all of them in this article, so we’ll just look at the most popular ones.

  • Black Neon Tetra
  • Neon Tetra
  • Cardinal Tetra
  • Lemon Tetra
  • Green Neon Tetra
  • Head And Tail Light Tetra
  • Glowlight Tetra
  • Ember Tetra
  • Disk Tetra
  • Diamond Tetra
  • Bucktooth Tetra
  • Blind Cave Tetra
  • Bleeding Heart Tetra
  • Black Skirt Tetra
  • Black Phantom Tetra

Neon Tetra Appearance

Neon tetras come in a variety of hues, including bright blue heads and backs, as well as a deep blue line from the eye to the tail and an iridescent red stripe on each side.

The body of a neon tetra is thin and torpedo-shaped, and the fish’s fins and tail are compact, translucent, and pointed.

Over the years, these species have been bred by breeders in different types that can only be found in captivity.

Types of neon tetras include:

  • Diamond head neon tetras: These fish appear to be wild neon tetras but have diamond-shaped heads.
  • Black neon tetras: The upper part of these species’ bodies is silver, the lower half is black and the line that runs from behind the eye to the tail is vertical.
  • Albino neon tetras – The appearance of this species is distinctive for its pale white bodies and pink eyes.
  • Longfin neon tetras – These fish have fins that are nearly twice as long as the wild neon tetra’s.
  • Golden neon tetras – Although they have a similar appearance to neon tetras, these fish are more colorfully patterned than the albino ones.

Male neon tetras are usually brighter in color than females.

They also have flatter bellies than females and straight blue stripes, while females have blue stripes that curve upward due to their rounded body shape.

When stressed, a neon tetra loses some of its bright colors and becomes faded.

In the dark, neon tetras become a dull violet-blue, but when exposed to light, they change to a brilliant blue-green.

Water Parameters

The first and most crucial factor in caring for tetra is water quality.

Tetras need certain water temperature, pH, hardness, and alkalinity levels to thrive, and if these parameters are not satisfied, the chances are that your black neon tetras will get sick or even die.

This section will talk about how to control water parameters in a neon tetra tank to make them live a healthy life.

1. Water Cycling

Tetras are extremely sensitive to changes in water quality. This means if your tank isn’t cycled regularly, you could lose all of your fish quite rapidly.

We recommend altering 10% of the water every week or 25% every two weeks for best results.

2. Water Temperature

Tetras require constant water temperature to keep their metabolism functioning properly.

The best temperature for tetra is between 75-78 degrees Fahrenheit.

If the temperature drops below 75 degrees Fahrenheit, the fish will become uncomfortable and anxious, and in severe cases, their immune systems can be weakened, making them prone to bacterial diseases.

3. pH Level and Alkalinity

In the wild, most neon tetras live in soft, acidic water. However, most aquarium species sold today are raised commercially in water that is often higher in pH and alkalinity than their native habitats.

In general, a pH range of 6.8 to 7.8, with alkalinity ranging from 3° to 8° dkH (50 ppm to 140 ppm) is ideal.

Tank Setup

1. Tank Size

Tetras are schooling fish that thrive in groups with at least 6 individuals.

A 10- to 20-gallon tank is appropriate for your tetra. However, as we always say, the bigger the better.

So if you can provide your tetras with a larger tank, don’t hesitate to do so.

2. Tank Heater

Tetras are tropical fish that require warmer temperatures to thrive.

While your aquarium may reach the desired temperature range for most of the day, it isn’t enough for our new Tetra friends.

Therefore, an aquarium heater is a must-have purchase, as it can keep your fish at a stable temperature.

There are many different heaters to select from and for sure the type matters.

Since different heaters have various wattages, when purchasing your heater, make sure you get the correct wattage for your tank by doing some research.

As a general guideline, you should aim for 2.5 to 5 watts per gallon.

3. Tank Filter

One of the most important pieces of equipment you should have in your aquarium is an aquarium filtration system.

Filters work by removing toxic substances from the water and promoting circulation in the tank.

Keeping neon tetras in unclean water would be the last thing you’d want to do since your cardinal tetra fish are sensitive and a higher concentration of waste can compromise their immune system.

This is why you must use a filter to keep your aquarium clean.

The size of the tank and the water volume has a big influence on which filter is best.

You should never put an overly strong filter in a little aquarium because it would prevent the fish from swimming freely.

At the same time, you should not use an underpowered filter for a large aquarium since a tiny filter will not be able to provide sufficient filtration in such a big tank.

4. Tank Lighting

In the wild, cardinal tetras receive 12 to 14 hours of light each day.

To keep your fish healthy, it’s important to imitate their natural habitat as closely as possible.

Providing your neon tetras with 12-14 hours of light will assist them to maintain a healthy circadian rhythm that helps to regulate their metabolism, energy levels, and appetite.

In a freshwater tank, a low-watt fluorescent light, usually between 18 and 40 watts, is sufficient.

However, if you want to keep live plants in your aquarium, you will need approximately 2 to 5 watts per gallon of water.

It’s advisable to set your lights on a timer so that your fish can get into a routine.

5. Tank Decoration

Wild neon tetras can be found in tropical streams with thick vegetation that includes floating plants and roots.

And as mentioned, the most essential step of keeping any fish is to replicate their habitat.

It’s recommended to decorate your green neon tetras tank with floating plants like hornwort and Java moss since tetras love hiding in the shade of these plants, which provide secluded, shaded refuge. 

Driftwood can also be used to offer hiding places for the fish and it looks really pretty in an aquarium.

Substrate is not a necessary addition to your tetra tank. However, a dark substrate, such as black sand, will make your neon tetra feel at home and complement its beautiful neon coloring.

Tank Mates

Tetras are the most peaceful fish of all freshwater species, and they get along well with other similar-sized community fish, but there are a few exceptions.

Serpae tetras, for example, can occasionally be nippy, especially when kept in insufficient numbers.

Others, such as Buenos Aires tetras, become quite large and energetic, which might scare smaller fish.

Good tank mates for neon tetras include:

  • Barbs
  • Dawes cichlids
  • Small catfish (like cory catfish)
  • Small, peaceful gouramis (like honey gouramis)
  • Other tetra species (like candy cane tetras)

Non-fish tank mates for neon tetras include:

  • Mystery snails
  • Shrimp (like ghost shrimp)
  • Crabs

Diet and Feeding

In their natural habitat, tetras are omnivores, which means they consume a wide range of foods, including meat and vegetation, such as insect larvae, small insects, algal matter, and other plant material.

You should replicate the tetra’s natural diet by offering your fish with a comparable variety of animal- and plant-based meals.

Bloodworms, daphnia, tubifex, and brine shrimp are all viable alternatives as live or frozen foods.

It’s important to mention that neon tetras have quite small mouths, so make sure to choose appropriately sized food.

Also, make sure your tetras get enough plant foods in their diet.

Feed neons tetras algae wafers, grapes, cucumbers, and strawberries up to three times a week.

Another thing to bear in mind is that overfeeding tetras may make the fish ill.

So follow a feeding plan and don’t fill the tank with too much food.


Tetras are difficult to breed since specific water conditions are required to induce mating. And this is why most novices fail at breeding them.

In this section, we will share some tips and tricks that we learned from breeding neon tetras over the past few decades.

How to Breed Neon Tetras

To breed tetras, follow these steps:

1. Select the Pair

Select a pair of healthy male and female tetras. The fish should be at least 12 weeks old, and ready to breed.

2. Place the Pair in a Breeding Tank

Wait till the evening, then place the tetras in a dedicated breeding tank.

Moving your tetras at night when there is no light is crucial because this will significantly reduce the stress on the fish and create the perfect conditions for breeding.

3. Adjust The Water Parameters

To replicate the wild, you need to make the water softer than normal.

The tank’s pH level should be adjusted to between 5.0 and 6.0, and the water temperature should be lowered to 75°F.

4. Add Soft Water to the Tank

After two days, if the tetras still haven’t spawned, add a large amount of soft water to the tank.

Adding more soft water will help to lower the stress levels of the fish and encourage them to mate.

5. Replace the Female

If this didn’t work, replace the female with another female and continue to adjust the tank parameters.

If breeding is successful, a male and female will breed behind a plant or in a cave, and the female will scatter up to 130 translucent neon tetra eggs across the substrate and plants in the tank.

6. Remove the Parents

Remove the parents from the aquarium as soon as you notice the eggs to prevent the fish from eating their young.

7. Keep the Tank Dark

Tetras are sensitive to light, so keep them in the dark for the first five days.

8. Feed the Babies

The baby tetras will be able to feed themselves for their first three days after hatching by eating the egg sacs.

However, when they are older, you must feed the newborn fish prepared fry food and baby brine shrimp for the next three months.

9. Place the Babies in a Home Tank

After three months, the babies are ready now to be transferred to the home tank with their parents and other fish species that are compatible with them.

Tetra fry care

Most new tetra parents are unable to handle the responsibility of raising the fry. They get stressed pretty easily and will eat their babies to protect them and most of the time, they don’t even realize that these eggs are their own.

In this case, protecting and raising the fry till they become free swimmers is your responsibility.

Baby tetras need a well-balanced diet to grow faster and larger.

We recommend feeding them a high protein diet that includes yolks and ground brine shrimp.

You can also pulverize food pallets and flakes into a fine powder and feed that to the fry.

Do this 3-4 times a day, but make sure not to overfeed them because this can lead to health problems.


Tetras are very sensitive to polluted water and they will show signs of stress and illness when the quality of your tank’s water changes or when it becomes too polluted.

The following are the three most frequent diseases that affect tetras:

1. Neon Tetra Disease

Neon tetra disease is a so-called neon tetra illness because it was initially identified in neon tetras.

This disease, which is caused by a Microsporidian parasite, causes restlessness, loss of coloration, cysts, and difficulty swimming.

When fish eat contaminated live foods infected with the parasite that causes neon tetra disease, the infection spreads and can wipe out an entire fish tank.

And due to the fact that there is no known treatment for neon tetra disease, all sick fish should be removed from the tank to avoid the condition spreading throughout the entire tank population.

2. Ich

Ich, also known as white spot disease, is a parasitic illness caused by the protozoan Ichthyophthirius multifiliis.

Fish with Ich have salt-like spots on their bodies, tails, and fins, and often scratch their bodies against hard surfaces to get relief from the itching.

To treat your fish from the ich, you need to cure your whole tank.

So, it is recommended to raise the temperature two degrees and add one spoonful of salt for every five gallons of water to the aquarium.

3. Fin and Tail Rot

Tetras kept in unclean water are at risk of developing fin rot and tail rot.

This illness begins at the fish’s extremities and works its way toward the body, causing the fins to become ragged and frayed.

If you detect that your fish have this disease, you should use antibiotics to treat it.

Last Words

Tetras are very delightful fish that will add a lot of color to your tank.

They are also hardy and easy to care for as long as you follow the tips presented here.

We hope you have enjoyed this article.

Do you still have any questions?

If so, please share them with us in the comment section below.