Swordtail Fish – Species Profile & Facts

Disclosure: I may earn a commission when you purchase through my affiliate links. As an Amazon Associate I earn from qualifying purchases. – read more

The Swordtail Fish is one of the huge number of species that fall into the family of livebearers. These are all freshwater fish that give birth to live fish that are ready to swim. This means that their eggs get fertilized internally.

There are many livebearers that are widely popular among fish enthusiasts. Swordtail Fish can adapt to various tank environments, which makes them easy to care for. Therefore, we can only encourage beginner fish keepers to start off with them.

While they are rather lively, they surely won’t harm any of their tank mates. The peaceful temperament and decorative looks of this species makes it a great addition to your fish tank. What makes them particularly attractive is their uniquely shaped tail.

The Swordtail Fish comes straight from American a Central American rivers. In the wild, they live in plant-rich waters which are even slightly salty sometimes. There is a wide range of aquarium fish that has been produced from this species via crossbreeding.

This is the kind of fish you can find in almost any fish store. In case you want to crossbreed them, you can do so by adding Southern Platy to your aquarium which is closely related to this breed.

Swordtail Fish Aquarium Requirements

Swordtail Fish Aquarium Requirements

Swordtail Fish Aquarium Requirements

Your fish thank has to mimic the rivers and streams of Central and North America. These are tropical areas where many plants surround the Swordtail Fish. Besides plants, also many rocks can be found around them.

The reason why rocks, plants and other decoration are necessary is because they use them for hiding. According to their behavior, they might want to hide from strong lights, rapidly flowing water and their tank mates. In community aquariums, other fish are usually the only thing they are concerned about.

Although some of them can be found in somewhat salty waters, it is not a good idea to add salt to the aquarium water. They tend to live longer in freshwater. If you want to do it anyway, avoid using kitchen salt because it is not for fish. You better add the real thing that you can buy in fish stores.

It is true that Swordtail Fish are easy to care for, yet you still need to provide them the environment they got used to in the wild. They don’t require a specific type of substrate because you will only see them swimming in the higher layers of the tank.

However, it is worth to mention that they got used to the sight of sandy river bottoms. Therefore, adding sand as a substrate is a great idea. Try not to cram your aquarium with rocks, plants and bogwood. While the Swordtail needs them, it also needs a larger area for swimming.

Now we are talking about a very small fish species, therefore they don’t need such a big tank. One Swordtail alone needs at least a 15-gallon tank. Each additional one needs another 5-6 gallons to live and thrive comfortably.

Water Parameters for Swordtails

Water Parameters for Swordtails

Water Parameters for Swordtails

Plants are so important for the Swordtail that we are probably going to mention them a few more times. The role they play in the water parameters is that they clean it nicely. They keep it fresh and oxygenated for the Swordtail Fish.

Here are a few of our suggestions for the plants: Java Fern, Anubias Nana and Dwarf Hairgrass. If you can get any of these, your Swordtail will be more than grateful. Now what is important for the water is to keep the pH somewhere between 7 and 8.4.

Furthermore, you should opt for a water hardness of 12-30 dGH while keeping the temperature between 70°F and °80°F. The average temperature you can measure in their natural habitat is 79 °F, just to give you a reference. These water conditions should be maintained at all times.

You should measure these parameters and change the water on a regular basis. Otherwise, your Swordtails can easily get sick. Despite the fact that they are living in rivers outside in the wild, they don’t require water flow at all.

Swordtail Fish Tank Mates

If you opt for the Swordtail Fish, you need to select other peaceful fish as tank mates. Being rather social species, they feel great in the company of other passive fish. For example, it is a good idea to put them in the same tank with Platies.

This breed is their close relative and it can be found in the same rivers. The great thing about Swordtails is that they don’t give you much of a headache when you need to choose tank mates. They can live comfortably with many different species.

The rule of the thumb is to avoid any fish that are aggressive and could potentially attack, bully or injure them. Therefore, most Chiclids are out of the question. Rosy Barbs, Pearl Danios and Mollies are great choices. These will accompany them in the mid-levels of the aquarium.

From the bottom dwellers, we recommend Otocinclus, Dwarf Corydoras and Zebra Loaches. The Swordtail gives you many ways to populate the whole tank with lively and peaceful fish that look amazing.

Feeding Swordtail Fish

Feeding Swordtail Fish

Feeding Swordtail Fish

There is no need to worry about it, as Swordtails are one of the least demanding when it comes to food. Out in the wild, they have little choice, eating only algae, insect larvae and the vegetation around them.

Obviously, at the fish store, you can choose from a wide range of foods that provide them proper nutrition.

What you should look for are nutritious, high-quality dry foods. Juvenile Swordtails require a lot of protein in order to grow in a desirable pace. While they grow, you should give them either frozen meat-based foods or love foods.

Since meat is not that easy to digest, you need to give them some plant-based food too. They can get enough fiber from it to facilitate their digestion. Swordtails don’t shy away from eating algae and pretty much every green vegetable you can find in the kitchen.

They are small species that need to be fed a small amount a couple times each day. In case you find a surplus of food after they eat, you better remove it before it pollutes the water.

Swordtail Fish Breeding

Swordtail Fish Breeding

Swordtail Fish Breeding

Swordtails don’t lay eggs. Instead, they give birth to live young after internal fertilization. In other words, this species is a livebearer.

The perfect conditions for the breeding to start are 80-82°F of water temperature, a properly cleaned tank and fresh water.

During the breeding period, you should give them nutritious food with an emphasis of proteins.

You will already know it is going to be a success when the male starts to swim together with the female. Expect a little bit of fin nipping to happen as well.

As this is going to be rather stressful for the females, you need to add more of them to the aquarium.

Then, the females will most likely choose the male that has the biggest sword and eventually get pregnant.

Once you discover a dark gravid spot around their swelling rear fin, it means that the fish is pregnant. Keep in mind that you should instantly separate the juveniles from their parents, otherwise they will eat them. While separate, you can give them some smaller foods.

Are Swordtail Fish Aggressive?

As long as the Swordtail Fish is in an ideal tank environment in a healthy condition, it is not aggressive at all. You can hardly find another species that is so peaceful in temperament and easy to care for at the same time. Of course, it is not impossible for them to get aggressive.

If you make the mistake of adding only male Swordtail Fish to your tank, then the tension is going to be high between their own species and other tank mates. This also applies to the situation when you add only one male to the aquarium. You should add more females to your tank in a 2 to 1 ratio and problem solved.

Also, the water conditions have to be stable in the fish tank. When this species experiences sudden changes, they get stressed. If you see your Swordtail Fish being more and more aggressive, then you know what to do. Make sure the water parameters are as constant as possible.

Do Swordtail Fish Need a Filter?

The main concern among aquarists is whether they can remove the filter without hindering the growth of their Swordtail Fish? The answer to this question is yes. While it is true that they prefer fresh water, this still doesn’t make it a must to add a filter.

You can run your tank without a filter, although you also need to compensate its absence. Installing a lot of plants is a great way to keep the water clean. However, in this case, you need to regularly check the water regularly for harmful chemicals.

Again, it is not a must to install a filter but it’s definitely a vital component of any aquarium. The reason why Swordtail Fish get along well without one is because they prefer calm waters in the wild. By removing the filter, there will be no currents generated in the tank.

It will also require you to change the water more frequently while still maintaining the ideal temperature for your fish. This also brings the necessity of measuring the pH level quite often. If all this maintenance is manageable for you, then it surely won’t be hard to take care of your aquarium without a filter.

Do Swordtail Fish Need Heater?

The Swordtail is a tropical fish; therefore, we can only recommend you to install a heater. It is not to say they can’t survive without it but if you want to keep them healthy and thriving, then definitely get one. Cold waters only make them uncomfortable and potentially sick.

The water temperature needs to range from 70°F up to 80°F in order to be optimal for the Swordtail Fish. In the South American rivers where they come from, it averages a 79°F. In colder waters, they won’t even have the appetite to eat and they will have less energy to move around.

Are Swordtail Fish Good for Beginners?

It is unique, it is beautiful and it’s perfect for beginners. The Swordtail is quite an adaptive tropical fish that doesn’t need much to strive. Of course, it is best to do your research and learn more about their needs and behavior.

It is peaceful and gets along well with plenty of other fish that are in the same tank. There are no complications you should be afraid during breeding season whatsoever. In a big enough aquarium with properly set temperature and enough plants, they will surely live a long and healthy life.

They are also not that many rules to follow if you want to keep more than one of them. Make sure to not keep only one male alone and there should be twice as many females than males. This is just to keep them lively and peaceful.

Putting a lid on top of the fish tank is mandatory to prevent your Swordtail from jumping out and landing on the floor. This is a rather spectacular species that is widely popular and also a great choice for beginners.

Wrapping Up

When it comes to Swordtail Fish, you can choose from a big variety color. If you want to populate your aquarium with a diverse community of fish, then this species is a must have. Whether you are a more experienced aquarist or a beginner, you will surely not regret getting one.

They look awesome, they don’t need much and they can thrive in the company of many different tank mates. Although they are not schooling species, a group of Swordtail Fish is especially amazing to look at.

If you are about to make a list of peaceful freshwater fish that you want to add to your aquarium, then don’t hesitate to add this one. All you need to do is to avoid keeping aggressive fish together with them. Since they breed on a regular basis, you will be surprised how quickly their numbers are going to grow.

Author Image Fabian
I’m Fabian, aquarium fish breeder and founder of this website. I’ve been keeping fish, since I was a kid. On this blog, I share a lot of information about the aquarium hobby and various fish species that I like. Please leave a comment if you have any question.
Leave a Comment

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