25 Best Freshwater Aquarium Fish Species (With Pictures) (2024)

If you plan to set up your own freshwater aquarium, you’ll need the best fish to inhabit it. This article will help you learn about the best freshwater aquarium fish species.

Any of the following species could be a good match for your tank. However, if you pick one or two species, ensure that you accommodate all their requirements, so they will thrive in the new aquarium.

Now, let’s begin with the first, and probably most popular freshwater fish.

1. Guppy Fish

• Scientific name: Poecilia reticulata
• Adult size: 1-2 inches (2.5-5 cm)
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 5 gallons (19 liters)
• Temperature: 74-82°F (23-28°C)
• Social behavior: Peaceful

Guppies are a popular choice among new aquarium enthusiasts because they don’t require extensive knowledge to care for them. All that is needed is a simple freshwater tank with multiple plants and a suitable substrate.

Guppies originate from South America, where they were first discovered in 1866. They are also known as Million Fish or Rainbow Fish.

This species is available in a variety of colors and patterns, including red, grey, blue, and many others. The shape of their tail also varies depending on the type. One thing is certain: every guppy looks stunning in a community tank.

Guppies are generally peaceful fish that coexist well with other species. They typically swim around throughout the day. If you notice them sitting in a corner or remaining still for an extended period, they could be sick or stressed.

2. Platy Fish

• Scientific name: Xiphophorus maculatus
• Adult size: 1.5-2.5 inches (4-6 cm)
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 10 gallons (38 liters)
• Temperature: 70-78°F (21-26°C)
• Social behavior: Peaceful

The Platy Fish is another excellent choice for beginner fish keepers. This species is easy to care for and looks great in virtually any community tank, thanks to its peaceful nature.

Platies can live up to 5 years if properly cared for, and most will grow up to 3 inches long. Like Guppies, Platies come in various colors, offering you plenty of choices.

Platies are generally omnivores, eating both plants and meat. Ensure their diet is balanced, with vegetables being the most significant part and some meat components. In their natural habitat, they consume various foods, with a preference for herbivorous options.

To keep your Platies content, provide an aquarium filled with plants where they can hide and replicate their natural environment.

3. Molly Fish

• Scientific name: Poecilia sphenops
• Adult size: 3-5 inches (8-13 cm)
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 20 gallons (76 liters)
• Temperature: 72-82°F (22-28°C)
• Social behavior: Peaceful

Mollies are a great choice for both beginner and experienced fish keepers. They are easy to care for, and any Molly will make a lovely addition to your freshwater tank. Mollies are typically community fish, coexisting peacefully with others.

However, if their tank mates are not peaceful, Mollies may become aggressive. Ensure that you only keep peaceful tank mates to avoid conflicts.

Like Platies, Mollies are also omnivores and enjoy a variety of foods. Worms, algae, and vegetables are all suitable choices. You can even give them vegetables from your kitchen, but make sure to cut them into small pieces for easy consumption.

Mollies are small fish, with most not growing larger than 4.5 inches. Keeping multiple Mollies in the same tank can help them feel more comfortable. With proper care, they can live up to 5 years.

4. Swordtail Fish

• Scientific name: Xiphophorus hellerii
• Adult size: 4-6 inches (10-15 cm)
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 20 gallons (76 liters)
• Temperature: 72-79°F (22-26°C)
• Social behavior: Peaceful

Swordtails encompass a diverse family of fish, available in numerous colors and shapes. A common characteristic of Swordtails is the sword-like tail found in all variations, which gives them their name.

Swordtails are popular because they are easy to care for. A 15-gallon aquarium is a good starting point, as Swordtails are not too large but are active swimmers. Covering your tank is recommended since Swordtails are known to jump.

Maintain the water temperature between 65 and 82 degrees Fahrenheit, and avoid sudden changes. Feeding Swordtails is simple, with options such as flake food, vegetables, worms, and shrimp.

5. Cory Catfish

• Scientific name: Corydoras spp.
• Adult size: 1-3 inches (2.5-7.5 cm), depending on the species
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 20 gallons (76 liters)
• Temperature: 72-78°F (22-26°C)
• Social behavior: Peaceful

The Cory Catfish, or Corydoras, is a favorite among freshwater tank owners. One main reason is their ability to consume large amounts of algae.

Cory Catfish are often used as aquarium bottom cleaner fish, scavenging for leftovers and algae. A single Cory can clean a 20-30 gallon tank by itself.

It’s best to keep multiple Cory Catfish in your aquarium, as they are peaceful community fish that get along well with most species. They are usually active during the day but can be active at night as well.

When keeping Corys, ensure you have at least a 10-gallon tank. They can thrive in larger aquariums, but a 10-gallon tank is suitable in most cases.

6. Bristlenose Pleco

• Scientific name: Ancistrus spp.
• Adult size: 4-6 inches (10-15 cm)
• Diet: Herbivorous
• Care level: Easy
• Minimum tank size: 30 gallons (114 liters)
• Temperature: 73-81°F (23-27°C)
• Social behavior: Peaceful

The Bristlenose Pleco is a common Pleco Catfish species often chosen over the Common Pleco due to its smaller size. A Bristlenose Pleco typically grows up to 5 inches long, much smaller than the Common Pleco, which can grow up to 24 inches.

Despite their smaller size, this species requires ample space to thrive. If you plan to purchase Bristlenose Plecos, ensure you have an aquarium with a 25-gallon capacity.

It is important to note that keeping two males in the same tank is not advisable as Bristlenose Plecos are territorial. Two males will constantly feel threatened by each other. It’s better to have one male and multiple females in the tank.

Like the Cory Catfish, the Bristlenose Pleco is also a bottom dweller, spending most of its time scavenging and eating algae at the bottom of the tank. In addition to tank algae, their diet should consist of sinking pellets (wafers) and simple vegetables.

7. Gourami Fish

• Scientific name: Trichogaster spp.
• Adult size: 2-6 inches (5-15 cm), depending on species
• Diet: Omnivorous
• Care level: Easy to Moderate
• Minimum tank size: 20 gallons (76 liters)
• Temperature: 74-82°F (23-28°C)
• Social behavior: Peaceful to Semi-aggressive

The Gourami is another large family of fish with many different species that work well in freshwater indoor aquariums.

Depending on the type of Gourami you purchase, you may need a larger or smaller aquarium. For instance, the Dwarf Gourami, a small species, can live happily in a 10-gallon tank. However, other species grow larger and may require a 30 or 40-gallon tank.

A common feature among all Gouramis is their preference for well-planted aquariums. Ensure your tank is filled with tall plants that reach the water’s surface, making them feel at home.

It is also important to remember that males can become aggressive towards one another, so it’s best to keep only one male in the tank along with multiple females.

8. Angelfish

• Scientific name: Pterophyllum scalare
• Adult size: 6 inches (15 cm)
• Diet: Omnivorous
• Care level: Moderate
• Minimum tank size: 30 gallons (114 liters)
• Temperature: 76-82°F (24-28°C)
• Social behavior: Semi-aggressive

The Angelfish is among the most beautiful species you can choose for your freshwater aquarium. They come in various shapes, sizes, and colors, and can be found in South America, in many rivers, including the Amazon.

Angelfish prefer slow-moving water, filled with driftwood and other hiding spots. To mimic this environment in your tank, include small caves and other hiding places.

Angelfish are omnivores, so their diet can include a variety of foods. They particularly enjoy worms and flakes specially made for them. However, you can also feed them simple vegetables sliced into small pieces.

Keep in mind that fully grown Angelfish may eat smaller fish in the tank. This doesn’t mean they are aggressive, but they will consume almost anything that fits in their mouths. To avoid this issue, choose tank mates that grow to a similar size.

9. Tetras

• Scientific name: Characidae family
• Adult size: 1-2 inches (2.5-5 cm), depending on species
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 10 gallons (38 liters)
• Temperature: 72-82°F (22-28°C)
• Social behavior: Peaceful

The Tetra Fish comprises a large group of different versions of the same Tetra species. Some examples include Neon Tetras, Rosy Tetras, Lemon Tetras, and Penguin Tetras.

One of the most popular choices is the Neon Tetra, a small fish that grows up to 1.5 inches long. Despite its small size, it is one of the most beautiful freshwater fish you can find and can live up to 8 years.

Tetras enjoy schooling together and spend most of their time swimming around in the tank, particularly in the water column. Their peaceful nature makes them a perfect addition to a community aquarium.

10. Rasbora Fish

• Scientific name: Rasbora spp.
• Adult size: 1-4 inches (2.5-10 cm), depending on species
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 10 gallons (38 liters)
• Temperature: 72-80°F (22-27°C)
• Social behavior: Peaceful

Similar to Tetras, Rasboras belong to a large family with many different species, including the Harlequin Rasbora, Brilliant Rasbora, and Clown Rasbora.

The Harlequin Rasbora is popular among fish keepers for its ease of care and sociable nature. This species lives in small groups and enjoys interacting with other tank mates. The Harlequin Rasbora is an excellent choice for beginner fish keepers.

Providing clean water and a balanced diet will ensure your Rasboras thrive in their artificial environment. If properly cared for, Rasboras can live up to 8 years.

When selecting tank mates for Rasboras, choose fish of similar or slightly larger sizes; larger species may view them as food.

11. Betta Fish

• Scientific name: Betta splendens
• Adult size: 2.5-3 inches (6-8 cm)
• Diet: Carnivorous
• Care level: Easy
• Minimum tank size: 5 gallons (19 liters)
• Temperature: 76-82°F (24-28°C)
• Social behavior: Aggressive (males), Peaceful (females)

Betta fish are a somewhat controversial species. While they are beautiful and sought-after fish that even beginners would like to own, their care can be complicated, making them a less suitable choice for beginners.

One of the main reasons people want to own Bettas is their unique appearance. They come in various colors, but their most notable feature is the large, flowing fin covering half of their body, which sets them apart from other species on this list.

However, their beauty comes with a price: Bettas rarely get along with others, including their own kind. When adding other species to the tank, proceed with caution. Compatible tank mates include Black Tetras, Catfish, Croaking Gouramis, Rasboras, and Poecilias.

12. Siamese Algae Eater

• Scientific name: Crossocheilus oblongus
• Adult size: 6 inches (15 cm)
• Diet: Herbivorous
• Care level: Easy
• Minimum tank size: 30 gallons (114 liters)
• Temperature: 75-79°F (24-26°C)
• Social behavior: Peaceful

The Siamese Algae Eater, true to its name, is primarily known for its algae-eating capabilities. Many people add this species to their aquariums to help control algae growth.

Siamese Algae Eaters are peaceful fish that do well in community tanks. As bottom dwellers, ensure other tank inhabitants won’t bother them.

These fish thrive in groups of 4 to 6 members but can also be kept individually or in pairs. Their omnivorous diet mainly consists of algae, but they should also be provided with sinking pellets and wafers.

13. Otocinclus Fish

• Scientific name: Otocinclus spp.
• Adult size: 1-2 inches (2.5-5 cm)
• Diet: Herbivorous
• Care level: Moderate
• Minimum tank size: 10 gallons (38 liters)
• Temperature: 72-79°F (22-26°C)
• Social behavior: Peaceful

Similar to Siamese Algae Eaters, Otocinclus fish are known for their algae-eating capabilities. Feeding them is relatively easy, but they are herbivores, so avoid giving them meat or meat-based products. Algae wafers available at fish stores are a good choice, typically feeding them one piece every two days.

If you prefer homemade food, green vegetables such as lettuce, spinach, and zucchini can be offered, cut into small pieces.

Otocinclus fish are a great addition to tanks containing small, peaceful freshwater fish, as they thrive in community settings.

14. Danios Fish

• Scientific name: Danio spp.
• Adult size: 1-6 inches (2.5-15 cm), depending on species
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 10 gallons (38 liters)
• Temperature: 64-79°F (18-26°C)
• Social behavior: Peaceful

The Danios are a large family of fish with various species, including Zebra Danios, Pearl Danios, and Queen Danios. Focusing on the Zebra Danios:

A 10-gallon tank is a minimum requirement for housing Zebra Danios. These fish grow up to 2 inches long, making their small size and peaceful nature ideal for community aquariums.

Unlike many other species in this article, Zebra Danios can thrive in both cold and warm water. Most Danios require water temperatures between 64 and 75 degrees Fahrenheit, eliminating the need for a heater in the tank.

A high-quality water filter is essential, as they require crystal-clear water to thrive. Make sure to invest in a reliable filter to maintain optimal water conditions.

15. Rainbowfish

• Scientific name: Melanotaeniidae family
• Adult size: 2-6 inches (5-15 cm), depending on species
• Diet: Omnivorous
• Care level: Moderate
• Minimum tank size: 20 gallons (76 liters)
• Temperature: 72-82°F (22-28°C)
• Social behavior: Peaceful

Rainbowfish are a popular choice among both beginner and experienced fishkeeping enthusiasts. These small fish coexist well with other community fish species; however, due to their size, it is essential to avoid housing them with larger fish such as Bettas.

As schooling fish, Rainbowfish should be kept in groups of at least 5 or 6 to feel comfortable in their new environment. Males will exhibit vibrant colors in the presence of females, making the group even more visually appealing.

Feeding Rainbowfish is relatively simple, as they are omnivores. You can provide them with earthworms, pellets, vegetables, or specially formulated food for their species.

Unlike some other fish on this list, Rainbowfish are not bottom dwellers. Ensure they have ample swimming space in the aquarium, as they enjoy moving around in groups. A 30-gallon tank is usually sufficient for a group of six Rainbowfish.

16. Clown Loaches

• Scientific name: Chromobotia macracanthus
• Adult size: 12 inches (30 cm)
• Diet: Omnivorous
• Care level: Moderate
• Minimum tank size: 75 gallons (284 liters)
• Temperature: 75-85°F (24-29°C)
• Social behavior: Peaceful

Clown Loaches are a popular choice among fish keepers due to their appearance and behavior. These schooling fish are active during the day and exhibit an orange body with v-shaped stripes on both sides, which gives them their name.

As schooling fish, Clown Loaches should be kept in groups of at least 3 or 4. They are peaceful and thrive in community tanks. Almost any other peaceful, group-loving fish species would make a suitable tank mate.

Unlike many other species mentioned, Clown Loaches are carnivorous. They consume both live and dry foods but prefer live options. Earthworms are an excellent nutrient source for Clown Loaches, but store-bought food is also suitable.

17. African Cichlids

• Scientific name: Cichlidae family (African)
• Adult size: 3-12 inches (8-30 cm), depending on species
• Diet: Omnivorous
• Care level: Moderate to Hard
• Minimum tank size: 30-100 gallons (114-378 liters), depending on species
• Temperature: 75-86°F (24-30°C)
• Social behavior: Aggressive to Semi-aggressive

African Cichlids are an excellent choice for those seeking vibrant colors in their aquarium. These beautiful fish come in a variety of colors and can make a community tank look stunning.

Depending on the species, African Cichlids can live up to 15 years, making them a suitable option for long-lasting freshwater environments. However, they are territorial and aggressive, which may cause conflicts with other active swimmers in the tank.

To minimize conflicts, choose tank mates that primarily dwell at the bottom of the tank, ensuring each species has its own space.

18. Ram Cichlids

• Scientific name: Mikrogeophagus ramirezi
• Adult size: 2-3 inches (5-8 cm)
• Diet: Omnivorous
• Care level: Moderate
• Minimum tank size: 20 gallons (76 liters)
• Temperature: 78-85°F (26-29°C)
• Social behavior: Peaceful

Ram Cichlids are another Cichlid species but differ in their behavior compared to African Cichlids. While the latter are aggressive, Ram Cichlids are peaceful and thrive with similarly peaceful companions.

Community tanks are perfect for Ram Cichlids, which can coexist with species like Platies, Corydoras, Guppies, Clown Loaches, and Tetras.

Ram Cichlids are omnivores and can be fed various foods, including small insects. Mosquito larvae and other small insect larvae can be offered, as well as vegetables.

19. Killifish

• Scientific name: Cyprinodontidae family
• Adult size: 1-6 inches (2.5-15 cm), depending on species
• Diet: Carnivorous
• Care level: Moderate
• Minimum tank size: 5-20 gallons (19-76 liters), depending on species
• Temperature: 68-80°F (20-28°C)
• Social behavior: Peaceful to Semi-aggressive, depending on species

Killifish are among the most beautiful fish species available for freshwater aquariums, with various types to choose from, all featuring vivid colors.

Most Killifish species are peaceful towards other fish species, making them excellent tank mates for many community fish species. However, male Killifish may display aggression towards other males in the tank.

In their natural habitat, most Killifish are carnivorous. Providing them with live crustaceans, insect larvae, and worms will help them meet their nutritional needs.

A well-balanced diet for Killifish should include food types such as Brine Shrimp, Daphnia, Mosquito Larvae, White Worms, Black Worms, and Tubifex Worms.

20. Discus Fish

• Scientific name: Symphysodon spp.
• Adult size: 8-10 inches (20-25 cm)
• Diet: Carnivorous
• Care level: Hard
• Minimum tank size: 55 gallons (208 liters)
• Temperature: 82-88°F (28-31°C)
• Social behavior: Peaceful

Discus Fish are considered a more challenging breed to keep, requiring attentive care. To successfully maintain Discus Fish, you need to ensure stable and clean water conditions, a water temperature of 84 degrees Fahrenheit, a pH level of 6.5, and a water hardness of 4.

Carnivorous by nature, Discus Fish can be fed dry or live food. They particularly enjoy bloodworms, pellets, flakes, and beef heart. The beef heart is a beneficial addition to their diet due to its high nutritional content.

However, it can also pollute the tank. To prevent this, offer it in small quantities and perform regular tank maintenance and cleaning.

21. Goldfish

• Scientific name: Carassius auratus
• Adult size: 6-14 inches (15-35 cm), depending on species
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 20-75 gallons (76-284 liters), depending on species
• Temperature: 65-75°F (18-24°C)
• Social behavior: Peaceful

Goldfish are one of the most popular freshwater fish species out there, if not THE most popular breed. There are many different varieties of Goldfish, which we will cover in general here.

Most Goldfish grow up to 6 inches long (though there are smaller ones) and live up to 10 years old if cared for properly. To house Goldfish, you need at least a 20-gallon fish tank. The water doesn’t need to be heated, as they typically live in colder environments.

Goldfish are a peaceful breed that works well in community tanks. Keep in mind, though, that some versions of Goldfish aren’t very fast swimmers. So, don’t house them with larger and quicker species, as they won’t be able to escape.

22. Oscar Fish

• Scientific name: Astronotus ocellatus
• Adult size: 12-14 inches (30-35 cm)
• Diet: Carnivorous
• Care level: Moderate
• Minimum tank size: 75 gallons (284 liters)
• Temperature: 74-81°F (23-27°C)
• Social behavior: Aggressive

If looks can be deceiving, the Oscar fish is a living example. This beautiful species gracefully swims in the tank. However, these creatures are quite aggressive towards other tank mates. Because they grow up to 12 inches long and are omnivores, you should be cautious when choosing tank mates to place with them.

Oscars are actually a type of Cichlid, so their aggressive behavior shouldn’t come as a surprise.

Most of their time is spent swimming in the middle regions of the aquarium, but they occasionally venture to the bottom in search of food. If you’re not an experienced fish keeper, it’s best to consider other fish for your tank.

23. Dwarf Puffer Fish

• Scientific name: Carinotetraodon travancoricus
• Adult size: 1 inch (2.5 cm)
• Diet: Carnivorous
• Care level: Moderate
• Minimum tank size: 5 gallons (19 liters)
• Temperature: 74-82°F (23-28°C)
• Social behavior: Semi-aggressive

As its name suggests, the Dwarf Puffer is a small fish breed common in home aquariums. Originating from India, it is usually sold at its full size of about 2.5 cm.

Due to its small size, the Dwarf Puffer doesn’t need a large tank. In fact, one Puffer needs just one gallon of water. Since Puffers are schooling fish, a 10-gallon tank can prove to be more than enough for them.

However, if you plan to add other companions to the aquarium, you should increase that number. Because Dwarf Puffers are peaceful by nature, they make great additions to community tanks.

But be cautious—don’t add larger fish that might mistake your Puffers for a snack.

24. Rainbow Kribs (Kribensis Cichlids)

• Scientific name: Pelvicachromis pulcher
• Adult size: 3-4 inches (8-10 cm)
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 20 gallons (76 liters)
• Temperature: 75-81°F (24-27°C)
• Social behavior: Semi-aggressive

If you want a proper community fish in your tank that won’t bother others, the Rainbow Krib is an ideal choice. This breed is unique because, unlike most Cichlids, it isn’t aggressive toward its tank mates.

Considered a dwarf Cichlid, the Rainbow Krib only grows up to 3 or 4 inches in size. Its natural habitat is the slow-moving rivers and deltas of West Africa, which you can easily replicate in your aquarium.

Although they are generally peaceful fish, Rainbow Kribs become quite aggressive during the breeding period. In this state, they will become territorial toward others in the tank.

25. Barb Fish

• Scientific name: Puntius spp.
• Adult size: 1-6 inches (2.5-15 cm), depending on species
• Diet: Omnivorous
• Care level: Easy
• Minimum tank size: 20 gallons (76 liters)
• Temperature: 68-79°F (20-26°C)
• Social behavior: Peaceful to Semi-aggressive, depending on species

The Barb is a diverse family, including various types of fish: Tiger Barb, Denison Barb, Gold Barb, Cherry Barb, Rosy Barb, and others.

Most Barb species are schooling fish that live in small groups. If you plan to buy some Barbs, be prepared to house 5 or 6 of them. This will help them thrive in the new aquarium.

One of the most recognizable is the Tiger Barb. This beautiful fish is known for nipping the fins of other fish in the tank. Because of this behavior, they are not suited for all types of community aquariums. However, other Barb species do not behave this way.

It’s best to keep them in small schools with other Barbs, not necessarily of the same type.

Comparing the Most Popular Freshwater Aquarium Fish Species

Here is a comparison table of the most popular aquarium fish species:

Conclusion

That’s all! You’ve learned about the best freshwater fish species for indoor aquariums. The next step is yours to take. Choose some of these species that work well together, and you can begin setting up the tank.

If you’d like, you can even start with just one breed and gradually work your way up to 3 or 4 different species. The choice is all yours!