Serpae Tetras are a wonderful freshwater fish that have a strong foothold in the aquarium scene. We had our first experience keeping one around five years ago, and have been a fan of them ever since.
Here’s why:
This species is not only beautiful, but they’re easy to keep. This makes them very beginner-friendly, or perfect for an aquarist who’s looking for something low-maintenance.
This guide will teach you the basics of Serpae Tetra care. We’ll cover things like tank mates, lifespan, diet, size, breeding, and more!
Table of Contents
- Species Summary
- Lifespan
- Appearance
- Size
- Serpae Tetra Care
- Tank Size
- Water Parameters
- Setting Up Their Tank
- Potential For Disease
- Serpae Tetra Tank Mates
- Breeding
- Wrapping Up
Species Summary
Colorful and incredibly active, the Serpae Tetra is a fish that will add some vibrancy to your tank. These fish have become quite popular among the aquarist community due to their playful attitudes and stunning good looks.
Scientifically known as Hyphessobrycon eques, these fish go by many names. They’re often referred to as Jewel Tetra or Callistus Tetra in the aquarium trade. Whatever you choose to call them, there’s no denying their beauty.

Serpae Tetras are endemic to the Amazon River basin in Argentina, Brazil, Paraguay, Peru, and Bolivia.
Typically, they can be found in slow-moving backwaters. In the murky waters of their natural habitat, they spend most of their time taking shelter from predators below. However, in a captive aquarium, they are the stars of the show.
Lifespan
The average Serpae Tetra lifespan in captivity is between 5 and 7 years. For this family of fish, that life expectancy is pretty standard.
This can be impacted by the usual factors. Poor water conditions, a lackluster environment, and a less-than-stellar diet can shorten the life of the Serpae Tetra dramatically.
Author Note: It’s possible for them to exceed this expected lifespan as well. Some owners who’ve given them fantastic care have seen them surpass the 7-year mark!
Appearance
Serpae Tetras are part of the Characin family. Thus, they have that familiar profile as some other types of tetra species. They’re relatively flat but have a tall frame and a trapezoidal shape.
The most visually striking aspect of the Serpae Tetra is their color. Most specimens take on a reddish-brown color. Base coloration can vary quite a bit with this species.
Some are more olive-brown while others take on a fiery scarlet hue. Either way, there’s one thing that all of these fish have in common. Their scales have a shiny finish that’s shimmers in the light. It creates a jewel-like luster that you can’t miss.
Beyond their base color, the Serpae Tetra has several distinct patterns on their bodies. The most noticeable is the black comma-shaped spot on their sides. Located just behind their gills, this spot can fluctuate in vibrancy. Some specimens even lose it altogether as they get older.

On the top of the fish, you’ll notice a large square-shaped dorsal fin covered in dark black. There may be some slight redness on the base of the fin. If you look very closely, many fish also have white edges on their dorsal fin.
This unique color pattern continues on the anal. However, rather than being covered in black, it’s predominantly red with black tips. A light smattering of white on the tips is pretty common as well, giving these fish an almost hand-drawn appearance in your tank.
The interesting thing about Serpae Tetras is that their colors can change multiple times throughout their lives. For the most part, the base colors remain unchanged. However, the vibrancy will improve or degrade based on their diet and environment.
There isn’t a ton of distinct differences between males and females. Usually, females are less vibrant than their male counterparts. They can also be a bit plumper ( especially true around breeding time).
Size
The typical Serpae Tetra size when fully-grown is around 1.75 inches in length. These are not very large fish!
It is possible for larger specimens to reach a full 2 inches, but this is pretty rare (especially in captivity). If you purchase your fish from a disreputable seller it’s far less likely that they’ll reach their maximum size.
Serpae Tetra Care
Serpae Tetra care is usually considered to be one of the easier tasks in the freshwater fishkeeping space. The water conditions they need are quite manageable and they require a straightforward diet. And even though they’re highly active, they will rarely show signs of aggression.
Of course, that doesn’t mean that you can ignore care guidelines. Like any fish, Serpae Tetras have some set conditions that you need to provide. Doing so will help the fish reach their full potential while reducing the risk of any health concerns.
Tank Size
Thanks to their small size, Serpae Tetras don’t need the massive tanks that most tropical fish require. Some aquarists have seen great success raising small groups in tanks as small as 10 gallons.
However, we recommend starting with a tank size of 20 gallons for the best results.
While they might be small, Serpae Tetras are big swimmers. They need plenty of space to explore. A larger 20-gallon tank provides that much-appreciated extra room.
Plus, it allows you to keep a larger group together, which is always preferred (more on this later).
Water Parameters
As we mentioned earlier, Serpae Tetra can be found in slow-moving backwaters. Usually, those habitats are calm, dark, and murky. They’re filled with blackwater, giving the fish plenty of opportunities to hide from predators.
Replicating that type of environment is crucial if you want to keep your fish healthy. You don’t have to go as far as creating true black water with a murky tint, but you can do your part to mimic the rest of the water conditions.
The natural environment of a Serpae Tetra is warm, soft, and slightly acidic. We recommend setting up your tank ahead of time and giving it plenty of time to cycle through. These fish are quite sensitive to major fluctuations in water conditions.
Giving your tank ample time to settle will ensure that your fish can get introduced to the new habitat without any issues. Here are some base parameter guidelines to follow for Serpae Tetras:
- Water temperature: 72°F to 79°F
- pH levels: 5 to 7.8
- Water hardness: 5 to 25 dGH
Setting Up Their Tank
Providing the right underwater landscape is just as important as closely monitoring water conditions. The key to keeping any fish species happy is to create a cozy habitat that closely resembles their environment in the wild.
The Amazon River basin is teeming with life. While you can’t always see what’s going on above the surface due to the murkier waters, those bodies of water are very dense with vegetation.
We recommend starting out with a dark sandy substrate.
A black or dark gray sand replicates muddy pond and river beds. Usually, bodies of water in the Amazon basin have a fine layer of decaying plant life at the bottom. The dark sand will mimic that.

Next, incorporate plenty of live plants throughout the tank.
Plants are very important for Serpae Tetras. Not only do they often snack on the plants, but they provide shelter. In the wild, these fish are usually seen congregating around tree roots.
They’ll do the same in your tank. Plants like Java Moss and Myriophyllum are good choices. Those plants offer great shelter while still letting the fish move through the leaves.
Arrange these plants in dense clusters around the edges of the tank. You don’t want to fill the middle of the aquarium with too many plants.
This is because Serpae Tetras need some room to swim. Filling the tank with too many plants may make that difficult.
Mix and match the plants with other forms of natural decor. Things like driftwood and rock formations are all good items that provide shelter.
Moving onto equipment, Serpae Tetras don’t have a ton of strict requirements when it comes to filtration. Any standard canister filtration system or hang-on-back unit will suffice. As long as it can effectively cycle the tank, it should do just fine.
The only thing to be wary of is the force of the return tube. Serpae Tetras prefer slow-moving waters, so make sure that it’s not too powerful. If it’s on the stronger side, you can place a plant or decorative item in front of the tube to break up the stream.
Author Note: Another important thing to consider is lighting. The murky waters of the Amazon basin don’t allow too much light in, so Serpae Tetras prefer things to be more subdued.
Luckily, the fish aren’t too picky with that regard as long as you have plenty of plants to block out light throughout the day.
Potential For Disease
We’re happy to report that Serpae Tetras don’t have any species-specific ailments that you have to watch out for. That said, these fish are susceptible to all the common freshwater ailments.
These include things like Ich, fungal infections, and skin flukes. You can easily avoid many common health conditions by simply staying on top of water conditions. Most diseases are a direct result of stress and poor living conditions.
With consistent monitoring and regular water changes, you should have no problems keeping your Serpae Tetras healthy.
Food & Diet
Serpae Tetras are omnivores by nature. In the wild, they typically eat plant matter and insect larvae floating on the surface of the water. In captivity, they are happy with just about anything you provide.
You can choose to feed your fish a regular diet of high-quality flakes or pellets. This can serve as the foundation of their diet.
It’s a good idea to supplement with some protein-rich foods as well (this will balance things out). The occasional snack of bloodworms, brine shrimp, and other live or frozen proteins are good as well.
Behavior & Temperament
For the most part, Serpae Tetras are peaceful. They are fast-moving fish that get along with several other fish species.
As we mentioned earlier, these are community fish that thrive in larger groups. When paired together, they’ll spend a lot of time exploring the tank.

Larger groups help make the fish feel more confident. They behave differently and will spend less time hiding when there are other Serpae Tetras around.
Typically, they stick to the middle and bottom of the aquarium. They’ll occasionally swim to the surface (usually during feeding time).
These fish do exhibit some unique swimming patterns. Rather than swimming elegantly throughout the habitat, they will swim in a jerky rhythm. They’ll swim in short bursts before resting and starting again.
This can prove to be problematic in some scenarios. Serpae Tetras have been known to show some slight aggression towards slow-moving with long fins. They may nip the fins of Angelfish or Bettas, so exercise caution.
Serpae Tetra Tank Mates
The best tank mates for Serpae Tetras are other Serpae Tetras. We recommend keeping a group of 5 to 7. These fish may fight amongst one another, but it’s usually no major cause for concern.
They tend to develop a pecking order within the group and will show some slight aggression towards those that are weaker. Keep an eye on the group and take out any aggressors that cause harm or make it hard for other fish to eat.
Aside from other Serpae Tetras, these fish are compatible with other fast-moving peaceful fish. It’s best to avoid slow fish that could be targeted for fin nipping. You should also avoid larger aggressive species that may try and eat your Serpae Tetras.
Here are some good tank mates to consider:
- Danios (our favorite is the Celestial Pearl)
- Pictus Catfish
- Bolivian Ram Cichlid
- Bristlenose Pleco
- Cardinal Tetra
- Cory Catfish
- Black Skirt Tetra
- Twig Catfish
- Bloodfin Tetra
- Swordtail Fish
Author Note: While some aquarists have had success keeping freshwater aquarium snails as tank mates with Serpae Tetras, we don’t recommend it. It doesn’t work out the vast majority of the time.
Breeding
Breeding Serpae Tetras is an easy process. Though, it must be done in a separate tank. This species shows no parental instincts at all and will be a danger to your baby fish almost immediately.
Create a separate breeding tank that’s decorated similarly to that of the primary tank. Incorporate lots of plants and consider using a breeding mop. Serpae Tetras are egg-layers that will scatter their eggs throughout the environment.
Thick vegetation and breeding mops will catch the eggs and keep them protected. As for water conditions, you can keep things on the softer side. The pH balance should be around 6.0. Warmer waters up to 80 degrees may be used to trigger the breeder process.
Before you move your group of adult Serpae Tetras into the breeding tank, condition them with some protein-rich snacks.
Live and frozen food will help to move the spawning process along. Once your females get plumper, you’ll know it’s time to start breeding.
Males will chase the females around, causing her to scatter eggs throughout the tank. The males will then fertilize those eggs. Hundreds of eggs can be laid at once.
You should keep an eye on the process and remove the adults immediately after they are done. They tend to try and eat eggs very quickly.
After about 2 days, the eggs will hatch. The baby fry will eat their egg sacs and grow a bit before swimmingly freely. At that point, you can provide baby brine shrimp and infusoria for food.
Keep your baby fish in the separate tank until they are big enough to eat dry flake food and fend for themselves.
Wrapping Up
Serpae Tetras are a fantastic species to keep in a freshwater tank. Plain and simple.
Honestly. they could be one of our favorite Tetras at this point (and that’s saying something). With their beauty and low-maintenance nature, they’re a good fit for just about everyone.
Give them a shot! You’ll be happy you did.
FAQs
Are serpae tetras easy to breed? ›
Serpae tetras are relatively easy to breed as pairs or in groups of roughly an equal number of males and females. The key to successful breeding is to set up a tank with the proper habitat for spawning and subsequent grow-out of the fry.
Do serpae tetras lay eggs? ›To breed these fish, they should be given a small, dedicated breeding tank planted with thick bunches of fine-leaved plants such as Myriophyllum on which they can lay eggs. Filtering through peat moss can also be helpful. The eggs hatch in about 2 days. The average lifespan for a serpae tetra is about seven years.
Are serpae tetras aggressive fish? ›Serpae tetras are notorious fin nippers. There's really no way to prevent a fish from doing what it does unless you separate it. See if you can return them to where you purchased them or possibly sell or give them to someone who has a tank that can handle their temperament.
Will tetras breed in a community tank? ›There are many species of tetras, however, and some of them are easier to spawn than others—in fact many hobbyists have tetras spawning in their community tanks, though the fry seldom survive.
How fast do baby tetras grow? ›Small fish fry usually takes three months or several years to become adult fish. Of course, it is not all the same but determined by the fish species. However, small fish may spend less time. And it is said that tetra fry can grow quickly with proper care and diet.
How many tetra fish should be kept together? ›You should always have at least six Neon Tetras in a group, otherwise, they can become stressed and aggressive towards one another. Around 8 to 12 fish in one group is usually when they are happiest.
How many tetras should you buy together? ›Tetras are schooling fish and therefore they live happily in groups. Therefore, in the case of tetras, the classic rule of THE MORE, THE MERRIER applies literally. However, if you are the kind of person who believes in numbers, then a minimum of 6 tetra fish is recommended.
Do Serpae tetras need a heater? ›They do best in soft, neutral to slightly acidic water with a pH of between 6-7.5 and temperatures between 72°-79°, so you may or may not need a heater for them. Serpae tetras do best in a more dimly lit environment and thrive in blackwater aquariums.
Can you tell the gender of tetra fish? ›Tetras. Tetras do have some differences between sexes, which vary based on the species. The females are a bit larger and plumper than males. Males are often more vibrantly colored and may have longer fins than their female counterparts.
How hard is it to breed tetras? ›Breeding ember tetras is fairly easy, and the eggs are not light sensitive, but the fry grow very slowly and may take up to 2 months to reach 1/4 inch in length. Soft water is recommended for spawning.
How long does it take for tetras to breed? ›
Add adult tetras to the tank and let nature take its course. Tetras typically breed within a few days. If the tetras aren't breeding, try adjusting the pH and temperature of the water in the tank.
What is the maximum size of serpae tetra? ›The typical Serpae Tetra typically grows up to 1.75 inches and sometimes up to 2 inches for the largest specimens. These are usually very small fish, and may not even grow up to 1.75 inches under stringent living conditions.
Why are my tetras nipping each other? ›A key indicator of aggression in neon tetras include fin nipping and separation. Neon tetras nip the fin of other fishes, fish with longer fins are more likely to get nipped. So whenever you notice your pet nipping other fish's fins, it is a sign of aggression. And it is often triggered by stress.
Do tetras eat their eggs? ›A single female tetra can lay anywhere from 60 to 130 eggs, which take approximately 24 hours to hatch. Once the eggs are laid and fertilized, return the adults to their regular tank as they will tend to eat the eggs or the fry once they hatch.
What does tetra breeding look like? ›Spawning will generally occur in the morning. The male will embrace the female during spawning, which will then release more than 100 eggs. The eggs are transparent and slightly adhesive and will stick to the plants. Remove the breeding pair as soon as the eggs are laid, as the parents will quickly eat the eggs.
How long do baby fish need to be separated? ›In about 4 to 6 weeks, the babies should be large enough to release into the main aquarium. But be sure the babies have grown larger than the mouths of adult fish. If it's not possible to set up a separate aquarium, drop-in breeders are a great alternative.
How many tetras can you put in a 10 gallon tank? ›As a general rule, you can keep 6 or 7 of them in a 10-gallon fish tank. Keeping any more than this is known as 'overcrowding' and is full of potential problems. But it should also be noted that neon tetra is schooling fish and prefer to be kept in larger numbers in bigger tanks.
Is it hard to breed black skirt tetras? ›Black skirts are very easy to breed, though you will need a separate breeding tank as they scatter their eggs. This tank should be large enough to comfortably house a pair of tetras or a group; if wanting to try breeding as a group, try putting six females and six males together.
How many serpae tetras in a 20 gallon? ›In a tank of 20 gallons, the best number would be 5 to 7 Serpae Tetra as they will chase and develop a hierarchical order within themselves. Overcrowding may lead to diseases and with nippy fish such as Serpae Tetra, the best amount would be 5 to 7, which can be increased slightly if the tank size is bigger.
Is it hard to breed Cardinal tetras? ›Breeding cardinal tetras is challenging at best. A separate breeding tank is important, and it must have stable water chemistry: a pH of 5.0 to 6.0, and very soft water of 3 to 5 dGH or below is essential. They will spawn in the evening, generally laying between 130 and 500 eggs.
How often do tetra fish mate? ›
Neon Tetras can typically breed twice every month. Eggs will usually hatch in around 24 hours and from then on, it's just a case of keeping them safe and feeding them the correct food.
Why do my tetras not breed? ›Adjust conditions if your neon tetras are not breeding.
If breeding is not happening, then check the pH and temperature of the water, soften the water a bit more, and adjust the lighting as needed.
The female tetra will lay her eggs after about 14 weeks. Some females can lay their eggs earlier if they are not properly cared for. Pregnancy is usually at the end of 14 weeks. A fully grown pair of these fish can live up to 2-3 years in captivity.
What is the best food for skirt tetras? ›Black Skirt Tetra Diet & Feeding
In fact, they usually eat anything that comes in their way, including plants and insects. They also love brine shrimp and bloodworms. In captivity, you can feed your Black Skirt Tetras commercial dry food, like pellets or flakes.
They do best in soft, neutral to slightly acidic water with a pH of between 6-7.5 and temperatures between 72°-79°, so you may or may not need a heater for them. Serpae tetras do best in a more dimly lit environment and thrive in blackwater aquariums.
What disease is common in Serpae Tetras? ›Ich (White Spot Disease)
Ich is just about the most common disease that affects freshwater tropical and coldwater fish. Ich is caused by the parasite, Ichthyophthirius multifiliis, a protozoan that is usually present in most aquariums. Ich doesn't attack healthy fish.
Serpae tetras are micro predators. Meaning they feed on small insect larvae, fish eggs, worms, tiny shrimp, and other small aquatic animals. Since they don't eat algae or plants you shouldn't feed them plant-based foods.
Where do tetras lay their eggs? ›Tetra eggs are hard to spot. They are small, spherical, and white or yellow. They often see adhering to moss or plant leaves and on the sandy floor. A single female tetra can lay between 60 and 130 eggs, which hatch in around 24 hours.
Can neon and Cardinal Tetras breed together? ›It is as long as a Neon Tetra but slimmer in profile. Since they are quite rare and always wild-caught, you'll never confuse the two unless you mix them in the same tank. You should never do this because they will interbreed with each other.
How many babies do cardinal fish have? ›Once the incubation period is complete, the babies swim out of the male's mouth—each a tiny replica of an adult Banggai cardinalfish. Out of the average 40 eggs in a clutch, about 20 babies are born.