Freshwater fish come in all kinds of colors, shapes and sizes and every type of freshwater fish has different needs. The Freshwater Fish Hub is your introduction to the wonderful world of keeping freshwater fish as pets.
What are freshwater fish?
Freshwater fish are species of fish that live in water with very low salt levels. Unlike saltwater fish – which live in the salty oceans and seas – freshwater fish live in ponds & lakes, streams & rivers, and wetlands. These bodies of water contain very low amounts of salt and freshwater fish are specially adapted to live in these low-salt environments.
What fish can live in fresh water?
Freshwater fish could not survive in saltwater and saltwater fish could not survive in freshwater. Understanding the difference between freshwater and saltwater fish is therefore very important.
There are over 10,000 species of fish that can live in fresh water. In fact, over 40% of all fish species live in these fresh water habitats. That’s a remarkably high number when you consider that fresh water makes up just 3% of the water on Earth.
The other 60% of fish species are saltwater fish. They live in the world’s oceans, which between them hold 97% of the water on Earth.
Only fish with specially adapted physiologies can live in fresh water. The scales of freshwater fish help to stop them from losing salt through their skin, while their kidneys reclaim salts from their waste before it is excreted from the body.
What fish can go in a freshwater tank?
There may be tens of thousands of freshwater fish species, but not all types of freshwater fish are suitable for the home aquarium.
Some freshwater fish simply grow too large for a fish tank, while others need conditions that are difficult or impossible to replicate at home.
Fish that can go in a freshwater tank are usually smaller varieties that have been bred for the pet trade.
When choosing freshwater fish for your tank, you need to think about what size tank you have and the specific needs of your chosen fish species, as well as their compatibility with other fish they may be sharing the tank with.
Below, we list 21 popular examples of freshwater fish for you to consider.
iStock.com/MirekKijewski
Freshwater fish examples
A list of freshwater fish species that are often kept as pets. Explore 21 popular types of freshwater fish, with pictures.
Angelfish
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Barbs
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Bettas
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Kenyi Cichlids
iStock.com/Mirko_Rosenau
Corydoras Catfish
A peaceful fish that will add interest to the bottom of a tank – as well as helping to keep it clean. Cory Catfish should always be kept in groups, where they will exhibit schooling behavior, never alone.
iStock.com/Przemysław Iciak
Danios
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Discus
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Goldfish
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Gouramis
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Guppies
Guppies are easily recognized by the male’s brilliant colorful tail. Guppies breed very easily, which makes them perfect for attempting to breed fish with your choice of colors and patterns.
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Hatchets
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Killifish
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Loaches
iStock.com/Juan Carlos Juarez Jaramillo
Mollies
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Platies
iStock.com/Juan Carlos Juarez Jaramillo
Plecostomus
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Rainbowfish
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Rasboras
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Roseline Sharks
iStock.com/Juan Carlos Juarez Jaramillo
Swordtails
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Neon Tetras
Tiny, colorful fish that do well in groups of as many individuals as you can safely fit in your tank. Neon Tetras enjoy heavily planted tanks and look great against the foliage.
iStock.com/Raghu_Ramaswamy
What is the best type of freshwater fish to have as a pet?
Our top pick for best type of freshwater fish to have as a pet is the Neon Tetra. We can’t think of a better combination of toughness, gentleness, small size, bright color and interesting behavior.
Though there are other options too of course. Any of these pet freshwater fish would make a great beginner choice:
- Danios
- Guppies
- Mollies
- Platies
- Tetras
We have 6 key criteria for choosing a great freshwater fish to keep as a pet and these fish tick all the boxes.
iStock.com/Raghu_Ramaswamy
Attributes of good pet freshwater fish
- Hardy – Hardy fish can survive a wide range of conditions, which makes them easier to care for.
- Peaceful – You don’t want to worry about your fish fighting and getting injured.
- Small – Smaller fish need less water, which means you can get away with a smaller tank.
- Beautiful – You’ll want your tank to look bright and beautiful, so its good for fish to have some color.
- Interesting – Beginners can quickly become bored of fish that aren’t very active.
- Compatible – Some fish are simply better than others at sharing a tank.
Related: What is Fresh Water?
Other popular freshwater fish often kept as pets include Goldfish and Bettas. They’re certainly good options, but with these fish, a little extra care is needed.
Bettas can be aggressive, particularly males defending their territory from other males.
And goldfish are not small fish. You may think goldfish are small, but that’s because the fish you see in pet shops are very young. Goldfish can grow to be 12 inches long, or even bigger!
If you choose a freshwater fish from our list of recommendations then you shouldn’t go far wrong. Though ultimately, the best type of freshwater fish to keep as a pet is personal to you. It depends on what you want, what size tank you have, and your experience and skill as a fish keeper.
What is the easiest freshwater fish to keep as a pet?
The easiest freshwater fish to keep as a pet would be a small, hardy fish such as the guppy, danio, tetra or molly.
Many people think that goldfish are also easy to keep, however they can grow to be very large and need a lot of tank space.
What freshwater fish are not aggressive?
Freshwater fish that are not aggressive include tetras, corydoras catfish, platies, mollies, roseline sharks and swordtails.
However, all fish have the potential to be aggressive sometimes. For example, when competing for territory, food or a mate.
Related: Overview of Yoyo Loach
What freshwater fish can be kept together?
Any freshwater fish that are not aggressive and that share similar water requirements can be kept together.
One good combination would be a community tank of live-bearers: guppies, platies, mollies, and swordfish. Perhaps with some corydoras catfish at the bottom of the tank too.
What do I need for a freshwater fish tank?
Essential aquarium equipment for a freshwater fish tank:
- Fish tank
- Water supply
- Water conditioner
- Filter
- Electricity supply
- Test kit (pH, ammonia, nitrite, nitrate)
- Thermometer
- Suitable fish
Optional items for a freshwater fish tank:
- Heater
- Air pump
- Lighting
- Substrate (gravel, sand, stones)
- Plants
- Decorations
It is possible to keep fish in a very bare tank, where all you would need is a filter and the ability to test and treat the tank water to ensure it stays within healthy parameters.
However, in reality, you will also need or want some items from the optional list. For instance, plants and decorations will make your tank more visually appealing and give your fish places to hide and explore.
Find out more about aquarium equipment and aquarium plants.
How much does it cost to set up a freshwater fish tank?
It’s impossible to say exactly how much it will cost to set up a freshwater aquarium, as it depends on the setup you choose.
The price will vary depending on the size of your tank, the kind of filter you need, and whether you buy other accessories such as air pumps and lighting.
Then there’s the cost of your fish, substrate, plants and decorations. And finally ongoing costs, such as food, water treatments and electricity.
We recommend researching and planning your tank carefully before buying anything. You can then add up the cost of everything you need any make sure it’s within your budget.
How hard is it to maintain a freshwater fish aquarium?
Maintaining a freshwater aquarium is not hard work. The biggest job is changing the aquarium water, but this shouldn’t be too much work as it’s best to change a small amount of water frequently rather than a large amount all at once.
You’ll also need to feed your fish, add water treatments and medicines as required, and maintain accessories such as your filter.
It’s important to remember that maintaining your aquarium isn’t a chore. It’s how you care for your fish and an important part of the fish-keeping hobby.
What kind of food do freshwater fish eat?
| Types of freshwater fish food | What is it? |
| Dry food | The classic fish food that most people think of, usually consisting of flakes, pellets or wafers. |
| Freeze-dried food | Foods that have been frozen and then had the water/ice removed. A popular example are freeze-dried bloodworms. |
| Frozen food | Food such as bloodworms and daphnia that has been frozen. You can then defrost it and feed to your fish. |
| Live food | The same foods that are often frozen and freeze-dried – such as bloodworms and daphnia – can also be bought and fed live. However, there is a risk of introducing diseases to your tank. |
| Fresh vegetables | Fish will happily eat various types of vegetable. Peas are particularly popular and can be good for digestion. |
What is the best food for freshwater fish?
There is no one food that is the best food to feed to freshwater fish. Like humans, fish will be healthiest if they have a varied diet containing a range of vitamins, minerals and nutrients. This means you should try to feed your fish a combination of dry food, frozen or freeze-dried food, and fresh vegetables.
Learn more about freshwater fish
And if you’d like to learn even more, we recommend exploring our freshwater fish articles or finding out more about saltwater fish, fish tanks, aquarium equipment, or aquarium plants.