Red Eye Tetra 101: Overview, Care Guide

Red Eye Tetra (Moenkhausia sanctaefilomenae) is a small freshwater fish popular among aquarium enthusiasts for its bright red eyes and torpedo-shaped body. Native to São Francisco, upper Paraná, Paraguay, and Uruguay river basins in eastern and central South America. This fish can grow up to 3 inches in length and does well in a community tank setting.

This guide will discuss the proper care and maintenance of Red Eye Tetra. We will cover tank size, water parameters, diet, and breeding topics.

So, whether you are a first-time fish keeper or an experienced aquarist, read on for all you need to know about keeping Red Eye Tetras in your home aquarium.

Species Summary

Scientific Name:	Moenkhausia sanctaefilomenae
Common Name:	Red Eye Tetra
Average Size:	2.75 inches
Life Span:	5 years
Origin:	Amazon River basin
Water Temperature:	72°F to 84°F
pH Levels:	5.5 to 8.5
Water Hardness:	4 to 8 KH
Tank Size:	20 gallons
Food:	Flake food, freeze-dried bloodworms
Breeding:	Egg scatters, guarded fry

Red Eye Tetra has a torpedo-shaped body and bright red eyes. This fish can grow up to 3 inches in length and is generally peaceful towards other fish.

Red Eye Tetra is a schooling fish and should be kept in groups of at least 5 individuals. They prefer a tank with plenty of plants and hiding spots and do their best in a well-filtered aquarium.

Red Eye Tetra Lifespan

The average lifespan of Red Eye Tetra is 5 years. However, these fish can live up to 8 years with proper care and maintenance.

Red Eye Tetra Size And Growth Rate

Red Eye Tetra grows to an average size of 2.75 inches. However, some individuals may grow up to 3 inches in length. They achieve sexual maturity at around 2 years of age.

Their growth rate is considered to be moderate. It takes Red Eye Tetras around 6-8 weeks to reach full size. However, they will continue to grow and develop for several months after that.

Red Eye Tetra Appearance

Red Eye Tetra is a small freshwater fish popular among aquarium enthusiasts for its bright red eyes and torpedo-shaped body. This fish can grow up to 3 inches in length and does well in a community tank setting.

Most of their body is silver, with a faint horizontal stripe that runs along their flanks. The most notable feature of these fish is their bright red eyes.

Their fins are clear or pale in coloration. The dorsal fin is slightly taller than the anal fin, and the tail fin is forked.

Females are typically smaller than males and have less-pronounced fins.

Red Eye Tetra Behavior & Temperament

Red Eye Tetra is a peaceful fish that does well in a community tank setting. They are schooling fish and should be kept in groups of at least 5 individuals.

These fish can be found in slow-moving rivers and streams in the wild. They prefer areas with plenty of plants and hiding spots.

In the home aquarium, they should be provided with a tank that has plenty of plants and hiding spots. A well-filtered aquarium is also recommended.

Red Eye Tetras are generally peaceful towards other fish. However, they may become territorial toward fish of the same species. If kept in a group, they will establish a hierarchy with a dominant male at the top.

Red Eye Tetra Breeding

Red Eye Tetras are egg scatterers who typically breed in groups of 6 to 8. The female will lay up to 100 eggs, which the male will then fertilize.

The fry will hatch after 24 to 48 hours and should be able to eat newly hatched brine shrimp or micro worms. The fry should be kept in a separate tank for the first few weeks of life.

Red Eye Tetra is an egg-laying fish that spawns in groups. They typically lay their eggs in areas with plenty of plants in the wild.

In the home aquarium, they can be bred in a separate tank or the main tank. If breeding in a separate tank, it should be at least 10 gallons in size and filled with water that is between 72°F to 84°F. The pH level should be between 5.5 to 8.0, and the water hardness should be 4 to 8 KH.

Red Eye Tetras are not difficult to breed and can be bred in a home aquarium. However, providing them with the proper environment and diet is important to ensure a successful spawn.

Some things that you will need to do to breed them include:

Conditioning the parents with live food.
Setting up a breeding tank with plenty of plants.
Adding a layer of peat to the bottom of the tank.
Maintaining water quality.
Removing the fry to a separate tank once they are born.

Following these steps, you should have no problem breeding Red Eye Tetras in your home aquarium.

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Red Eye Tetras Shedding And Body Patterning

Red Eye Tetras are known to undergo metachromatic leucophore (ML) shedding. This is when the fish sheds its outer layer of skin, which contains pigment cells called chromatophores.

The fish’s body patterns and colors will change as the skin sheds. This process is thought to help the fish evade predators and parasites.

What does the fry look like?

The fry of Red Eye Tetra is tiny and delicate. They are born without color and typically have a clear or white body.

As they grow, they will start to develop their characteristic red eyes. Additionally, their body will begin to develop the black horizontal stripe typical of adult Red Eye Tetras.

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Red Eye Tetras Gestation Period And Pregnancy Symptoms

The gestation period for Red Eye Tetras is around 21 days. During this time, the female will develop a rounded belly as her eggs mature.

Once the eggs are ready to hatch, the female will release them into the water. The fry will typically hatch 24-48 hours later.

After they hatch, moving the fry to a separate tank is essential. This is because they are tiny and delicate and can easily be eaten by adults.

Additionally, the fry needs special care and attention to ensure proper growth and development.

Red Eye Tetras Eggs And Incubation

Once the eggs are laid, they will need to be incubated to hatch. This can be done by either the parents or by using an incubator.

If you are using an incubator, it is important to maintain the water temperature at around 80 degrees Fahrenheit. Additionally, the pH level should be kept between 5.5 and 7.0.

The eggs will typically hatch 24-48 hours after they are laid. Once they hatch, removing the fry to a separate tank is important. This is because they are tiny and delicate and can easily be eaten by adults.

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How Are They Different From Other Tetras

Red Eye Tetras are known for their striking red eyes. This is a unique characteristic that sets them apart from other tetra species. Additionally, Red Eye Tetras are typically smaller in size than other tetra species. They also have a lifespan of 5 years, which is shorter than most other tetra species.

Care Guide

Red Eye Tetra is a relatively easy fish to care for. They are hardy fish that can tolerate a wide range of water conditions. However, it is essential to provide them with a well-filtered aquarium and plenty of hiding spots.

Here, we will share everything to give your Red Eye Tetra the best care.

Tank Size

As mentioned before, Red Eye Tetras do best in tanks of at least 20 gallons. This is because they are active swimmers and need plenty of room to move around. Additionally, they should have plenty of plants and hiding spots.

Red Eye Tetras are typically found in the upper and middle regions of the tank. This is because they are active swimmers and prefer to be in the open water.

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Tank Mates

Red Eye Tetras are generally peaceful fish that can get along with most other fish. They are, however, more sensitive to changes in water quality and temperature than some of the other tetra species.

Additionally, they prefer to live in slightly acidic conditions. Because of this, it is important to choose tankmates carefully.

Some good tank mates for Red Eye Tetras include:

Lighting

Red Eye Tetras do not require special lighting. However, it is important to provide them with a well-lit tank. This will help to show off their beautiful colors and make them feel more comfortable in their environment. The ideal light for Red Eye Tetras is between 6500K and 8500K.

Heater

Red Eye Tetras prefer water that is between 72°F to 84°F. So, it is important to provide them with a heater to maintain these temperatures. Additionally, it is important to have a thermometer in the tank to monitor the water temperature.

Some suggested heaters are:

TetraTec TH Series Submersible Aquarium Heater
Eheim Jager Aquarium Thermostat Heater
Hydor ETH Inline External Aquarium Heater

Filter

Red Eye Tetras are sensitive to changes in water quality and prefer to live in slightly acidic conditions. Because of this, it is important to choose a filter that will help to keep the water clean and stable.

Some good choices for filters are:

Tetra Whisper EX Power Filter
Fluval External Filter
Eheim Canister Filter

Gravel Vacuuming

Red Eye Tetras are sensitive to changes in water quality and prefer to live in slightly acidic conditions. Because of this, it is important to perform regular gravel vacuuming. This will help remove any debris or waste accumulated in the tank.

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Ammonia levels

Red Eye Tetras are sensitive to changes in water quality and prefer to live in slightly acidic conditions. Because of this, it is important to make sure that the ammonia levels in the tank are always at 0 ppm.

Nitrite levels

Red Eye Tetras are sensitive to changes in water quality and prefer to live in slightly acidic conditions. Because of this, it is important to make sure that the nitrite levels in the tank are always at 0 ppm.

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Nitrate levels

Red Eye Tetras are sensitive to changes in water quality and prefer to live in slightly acidic conditions. Because of this, it is important to keep the nitrate levels in the tank as low as possible. The ideal nitrate level for Red Eye Tetras is between 20 and 40 ppm.

Oxygen Levels

Red Eye Tetras require high levels of oxygen in the water. The ideal oxygen level for Red Eye Tetras is between 6 to 8 ppm. A high level of oxygen in water can be provided by using an air pump and stone.

Protein Skimmer

A protein skimmer is not a requirement for Red Eye Tetras. However, it is a good idea to use one to keep the water quality high.

Red Eyes Tetra Food & Diet

Red Eye Tetras are omnivorous and will eat a variety of different foods. However, they prefer live and frozen foods. Some good choices for food are brine shrimp, bloodworms, daphnia, and krill.

Red Eye Tetras should be fed 2-3 times per day. It is best to provide them with small amounts of food at a time. This will help to keep the water quality high and prevent overfeeding.

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Food & Diet To Avoid

Red Eye Tetras should not be fed flake food or pellet food. These foods do not contain nutrients. Additionally, these foods can pollute the water and lead to health problems.

Aquascaping For Red Eye Tetras

When aquascaping for Red Eye Tetras, it is important to create a lot of hiding places. Red Eye Tetras are shy fish who appreciate plenty of hiding places. This can be accomplished by using driftwood, rocks, and plants.

It is also important to create a lot of open space in the tank. Red Eye Tetras need plenty of room to swim and explore.

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Red Eye Tetras Potential Fish Diseases

Red Eye Tetras are relatively hardy fish. However, they are susceptible to a few diseases. Red Eye Tetras can get diseases such as Ich, Velvet, and Fin Rot. It is important to quarantine new fish before adding them to the tank.

This will help to prevent the spread of disease. It is also essential to perform regular water changes and to keep the tank clean. This will help to prevent disease.

Ich: Ich is a parasitic disease that can be deadly to fish. Symptoms of Ich include white spots on the body, lethargy, and increased breathing. Ich can be treated with a wide variety of medications.
Velvet: Velvet is a parasitic disease that can be deadly to fish. Symptoms of Velvet include gold or yellow patches on the body, lethargy, and increased breathing. Velvet can be treated with a wide variety of medications.
Fin Rot: Fin Rot is a bacterial disease that can be deadly to fish. Symptoms of Fin Rot include frayed or ragged fins, lethargy, and decreased appetite.
Hole In The Head: Hole in the Head is a disease that affects the head and gills of fish. Symptoms of a hole in the head include white spots on the head and gills, lethargy, and increased breathing.
Dropsy: Dropsy is a disease that causes the fish’s body to swell. Symptoms of Dropsy include a bloated abdomen, lethargy, and increased breathing.
Swim Bladder Disease: Swim Bladder Disease is a disease that affects fish’s swim bladder. Symptoms of Swim Bladder Disease include floating upside down, difficulty swimming, and lethargy.
Tail or fin rot: Tail or Fin Rot is a disease that affects the fins and tail of fish. Tail or Fin Rot symptoms include frayed or ragged fins, lethargy, and decreased appetite.

It is important to note that some diseases are contagious and can be spread to other fish in the tank. It is important to quarantine sick fish and to consult a veterinarian if necessary.

The best way to prevent fish disease is to practice good aquarium husbandry. This includes performing regular water changes, keeping the tank clean, and quarantining new fish. It is also important to feed a nutritious diet and to provide a stress-free environment.

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Treatment And Medications For Diseases

Copper Sulfate: Copper Sulfate is a medication that is used to treat a variety of diseases. Copper Sulfate can be deadly to fish if not used properly. It is essential to consult a veterinarian before using this medication.
Formalin: Formalin is a medication that is used to treat a variety of diseases. Formalin can be deadly to fish if not used properly. It is essential to consult a veterinarian before using this medication.
Malachite Green: Malachite Green is a medication that is used to treat a variety of diseases. Malachite Green can be deadly to fish if not used properly. It is important to consult a veterinarian before using this medication.
Nitrofurazone: Nitrofurazone is a medication that is used to treat a variety of diseases. Nitrofurazone can be deadly to fish if not used properly. It is important to consult a veterinarian before using this medication.
Methylene Blue: Methylene Blue is a medication that is used to treat a variety of diseases. Methylene Blue can be deadly to fish if not used properly. It is important to consult a veterinarian before using this medication.
Metronidazole: Metronidazole is a medication that is used to treat a variety of diseases. Metronidazole can be deadly to fish if not used properly. It is important to consult a veterinarian before using this medication.
Kanamycin: Kanamycin is a medication that is used to treat a variety of diseases. Kanamycin can be deadly to fish if not used properly. It is important to consult a veterinarian before using this medication.
Tetracycline: Tetracycline is a medication that is used to treat a variety of diseases. Tetracycline can be deadly to fish if not used properly. It is important to consult a veterinarian before using this medication.
Ampicillin: Ampicillin is a medication that is used to treat a variety of diseases. Ampicillin can be deadly to fish if not used properly. It is important to consult a veterinarian before using this medication.
Levamisole: Levamisole is a medication that is used to treat a variety of diseases. Levamisole can be deadly to fish if not used properly. It is important to consult a veterinarian before using this medication.

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Advantages Of Having Red Eye Tetra In Your Tank

Red Eye Tetra is a peaceful and hardy fish that makes a great addition to any freshwater tank. They are relatively easy to care for and are compatible with most other fish.

Red Eye Tetras are active fish that add color and movement to the aquarium. They are also relatively easy to breed in the home aquarium.

Peaceful: Red Eye Tetra is a peaceful fish suitable for a community tank.
Hardy: Red Eye Tetra is a hardy fish that can tolerate many water conditions.
Easy to breed: Red Eye Tetra is an easy-to-breed fish, which makes them a good choice for breeders.
Active: Red Eye Tetra is an active fish that will add movement to your tank.
Fun to watch: Red Eye Tetra is a fun-to-watch fish that will add interest to your tank.
Not expensive: Red Eye Tetra is not an expensive fish, which makes them affordable for most people.
Beautiful: Red Eye Tetra is a beautiful fish that will add color to your tank.
Can be kept in groups: Red Eye Tetra can be kept in groups, which makes them ideal for community tanks.

Disadvantages Of Having Red Eye Tetra In Your Tank

May eat live plants: Red Eye Tetra may eat live plants, which can be a problem for some aquarium owners.
May nip at the fins of other fish: Red Eye Tetra may nip at the fins of other fish, which can be a problem in community tanks.
Requires a tank with a cover: Red Eye Tetra requires a tank with a cover, as they are known to jump out of tanks.
Can be aggressive towards other fish: Red Eye Tetra can be aggressive towards other fish, which can be a problem in community tanks.
Not suitable for nano tanks: Red Eye Tetra is not ideal for nano tanks, as they require a larger tank.
Not suitable for beginners: Red Eye Tetra is not ideal for beginners, as they require more care than some other fish.
Can be difficult to find: Red Eye Tetra can be challenging to find, as they are not as common as some other fish.
Can be expensive: Red Eye Tetra can be expensive, as they are not as common as some other fish.
Requires a lot of care: Red Eye Tetra requires a lot of care, as they are delicate fish.

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Conclusion

Red Eye Tetra is a peaceful and hardy fish that makes a great addition to any freshwater tank. They are relatively easy to care for and are compatible with most other fish. Red Eye Tetras are active fish that add color and movement to the aquarium.

They are also relatively easy to breed in the home aquarium. However, they may eat live plants and nip at the fins of other fish, so they are not suitable for all aquariums.

They also require a larger tank than some other fish, which is unsuitable for nano tanks. Red Eye Tetra is a beautiful and fun-to-watch fish that can be a great addition to your freshwater tank.

Red Eye Tetra 101: Overview, Care Guide | Updated 2024

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