12 Most Popular Aquarium Fresh Water Fish Species 

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aquarium fresh water fish species

There are hundreds to choose from when you are designing or adding to your aquarium, but what are some of the most popular aquarium fresh water fish species? It can almost be overwhelming to have to choose what fish you want to put in your aquarium! 

In fact, there are believed to be about 30,000 different species of freshwater fish!

After years of experience working in the fish and aquarium industry and after having done plenty of my own personal research, I can confidently say that there are several species of fish that are more popular than others within the freshwater aquarium community!

This article will discuss the 12 most popular freshwater aquarium species today. 

Aquarium Fresh Water Fish Species – Our Top 12 Picks


Platy fish

Platys are, without a doubt, one of the most popular freshwater aquarium fish. They are considered to be very hardy and able to withstand less than perfect tank conditions, which can make them a great fish for beginners.

Most platys are between 2 to 3 inches when fully grown, but dwarf platys are bred to be as small as just one inch. In their native habitats in Central America and Mexico, there are just a few kinds of platys, but thanks to selective breeding, there are dozens of different kinds of platys. Just a few examples include the red Mickey Mouse platy, the Malibu sunset platy, and even a Dalmatian platy. 


Tetras are a very popular type of schooling fish that do well in most peaceful freshwater aquariums. There are dozens of different kinds of Tetras. Their natural habitats include much of the Americas, especially in the Amazon river basin and the water systems around, but some can also be found in Africa.

A few examples include the Black Skirt Tetra, Neon Tetra, Bleeding Heart Tetra, and blue Tetra.

One of the most interesting things about Tetras is how variable some of the different types are in size. For example, the Black Skirt Tetra is much longer and wider than the Neon Tetra. Black Skirts can grow up to three inches, while Neons are only about 1.5 inches in length. 


This fish is sometimes called a suckermouth catfish or a common pleco. There are more than 150 different kinds of Plecostomus! Those most commonly sold in pet stores are the suckermouth catfish and are often recommended for beginner aquarium enthusiasts as they do an amazing job of cleaning the tank!

Some people even refer to them as the janitors of the tank, as they will eat anything on the bottom of the tank and even the scum that can grow on the sides of the tanks.

These fish have quite long lifespans when properly cared for and can live for up to 15 years.

Depending on the species, they can also grow from anywhere between 1.5 inches to as long as 12 inches in length! 


These fish, native to South America, are great low maintenance small beginner fish. Males are usually smaller than females and only measure about an inch in length, whereas females can get as big as two and a half inches in length. There are dozens of varieties, including the fantail guppy, the veiltail guppy, the double swordtail guppy, and more. Males and females are usually easily distinguishable from one another. The males tend to be smaller and more colorful, but the females tend to be much bigger but with less bright coloring. Guppies are especially popular because of their small size. Small groups can be kept in much smaller aquariums that are far less intimidating for beginners. 


Mollies are another great lower-maintenance type of freshwater fish with tons of varieties in size and color. A few examples include the black molly, lyretail molly, dalmatian molly, and the balloon molly with its notoriously round underbelly.

All of these have been selectively bred in captivity to enhance the characteristic traits of each species.

Mollies can be fairly large in size and range anywhere from 3 to 6 inches in length. While there are a great many variations within the different kinds of aquarium mollies, those found in the wild are usually a dull silvery-gray color.

With proper care in a peaceful aquarium, these hardy fish can live for as long as five years. 


Rainbow fish are another popular freshwater aquarium species, possibly made even more popular thanks to the famous children’s book!

Though maybe not quite as colorful as the multicolored fish in the book, real rainbow fish are still beautiful creatures. In the wild, rainbowfish can be found in the waters of Australia, parts of New Guinea, Indonesia, and Madagascar. Most species of rainbowfish are between four and five inches.

Like many of the fish on this list, rainbowfish are highly social creatures and love company, so it is best to keep them in groups with not only just multiple rainbowfish but with other friendly freshwater aquarium species as well. 

Clown Loach 

Clown Loaches can be found in the waters of Indonesia. These fish are very active throughout the day, which in addition to their beautiful coloring, is one of many reasons that they are so popular among aquarium enthusiasts.

Another reason for their popularity is that they actually help maintain the ecosystem of the aquarium by eating pest snails. They do require a fairly large tank, as they can grow as long as twelve inches!

They are also a bigger commitment than many of the fish on this list, as they can live for as many as 10 to 25 years.

Most people will invest in a very large tank early on for these fish, so they have plenty of room. 


Danios are another popular choice for many freshwater aquarium enthusiasts thanks to their small size and their hardiness. Some can grow to be anywhere from 1.5 to 4 inches in length, but most grow to be somewhere between 1.5 and 3 inches in length.

There are several different species of danios, including the dwarf spotted danio, the zebra danio, the white cloud mountain minnow, the pearl danio, and the giant danio. In proper condition and with proper care, these fish can live for up to five or more years. These are highly social fish and do best when kept in a large group of the same or similar-sized fish. 


The Otocinclus is another species of catfish that people like to use to help keep their aquariums in pristine condition. These fish are peaceful and only measure to be about as long as one to two inches.

Though they are friendly, they should never be left with much larger or more aggressive fish. This fish is also sometimes called the dwarf armored catfish, the dwarf sucker, or the oto. They can live as long as three to five years. In the wild, they are most often found in slow-moving water.

One especially interesting fact about otos is that they actually have a sort of armor on their body that actually helps protect them from other fish. Despite this, though, they still do best in peaceful and friendly aquariums. 

 Cory Catfish 

Cory catfish are another great bottom dweller that do an excellent job of keeping their tank clean. They’ll often graze along the bottom in the hope of finding some leftover uneaten food that they can munch on.

Cory catfish are social creatures and prefer to have at least one other Cory catfish for companionship, if not more. When they are cleaning and feeding on the bottom of the tank, they often like to stick close together. This may have something to do with the fact that they are on the small side for a catfish, and they find safety in numbers.

Cory catfish can be as small as one inch in length up to four inches in length. Another feature that they have that helps provide them protection is sharp spines in their fins that actually will give off a mild venom when the fish is stressed.

These are fish that definitely won’t want to be pet! 

Betta fish

Betta fish are another example of one of the most popular fish to keep due to their long flowing fins, gorgeous colors, and overall hardiness. However, it is important to note that two Bettas cannot be kept together.

This will only lead to fighting. Bettas can, in some cases, do well with other fish from different species, but they most often thrive in a tank by themselves. 


Of course, we can’t forget to mention goldfish! These are, without a doubt, one of the most popular freshwater fish for aquariums today. There are believed to be well over 200 different species of goldfish. Just to mention a few, some of the most popular ones are the Comet goldfish, the Blacktail Moor, and the Oranda goldfish.

Unlike the other fish on this list, goldfish do best when kept in an aquarium with their own species. This is not because they are aggressive, but it is more so because goldfish have different temperature requirements than other freshwater fish. 

Final thoughts 

There are hundreds, if not thousands, of different freshwater species that can thrive in an aquarium setting. It is just a matter of picking your favorite! Some are more popular because of their unique looks, like the Cory Catfish, while others are adored for their beautiful colors, like guppies, platys, or rainbow fish.

Most of the fish mentioned in this list are social creatures and will do well in a community tank with other peaceful fish, so they are especially great options for beginner aquariums. But even folks with tons of experience with freshwater aquariums will always go back to some of the most popular ones.

They are popular for a good reason, after all! 


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