Which Fish Can Live In A Freshwater Tank?

13 min read

Do you know that one of the benefits of keeping an aquarium is that it can help you relieve stress? Not only does it help you relieve stress but it is also an excellent way to decorate your home and office. One of the common questions that people ask is “What kind of fish can live in a freshwater tank?”

The simple answer is that there are a lot of fish species that can live in a freshwater fish tank.

Having an aquarium with different species of fish and other aquatic animals is an excellent way to bring life into any room. Now that you know some of the benefits of having an aquarium you may have some questions.

There are a lot of freshwater fish species that have been reared in the aquarium successfully.

However, you need to note that not all freshwater fish will survive in an aquarium so it is important to know what type of fish you are bringing into your freshwater tank. There are lots of factors to be considered since they won’t be living in their natural home. Some fish species will find it difficult to adapt to the new life in the aquarium.

Such fish, although it is a freshwater fish, will not do well in an aquarium. Some fish will refuse to eat if they are moved from their natural home to a freshwater tank.

Fish are cold-blooded animals and what this simply means is that fish cannot regulate their body temperature but they rely on the temperature of the water surrounding them.

Based on the temperature of the water, freshwater fish can be classified as either coldwater fish or warm water (tropical) fish. This is important especially when you want to combine more than one fish.

You should note that you cannot combine fish that require different temperatures in the same tank. You are going to see some examples of coldwater fish and warm water fish that can live in a freshwater tank.

Coldwater Freshwater Fish Species

Coldwater fish species are those fish that can survive low temperatures, usually below room temperature. These fish do not require a heater in the water tank.

High temperatures may increase the metabolism of most coldwater fish and thereby reduce their life span. Sometimes, the term coldwater fish is simply used to describe any aquarium fish that do not need a heater.

1. Common Goldfish

goldfish live in a freshwater tank

Goldfish is the first on the list among the coldwater fish species. These small golden fish are one of the most known aquarium fish. They are in the same family as the common carp.

Their color is one of the reasons why they are an excellent candidate for an aquarium. However, apart from their color, other things make them very interesting to have in an aquarium.

  • They are super intelligent and watching them can be exciting.
  • They have an excellent vision and with time, they can tell the difference between their owner and a stranger.
  • They will hide when they see other people approaching the tank but when their owner comes close to the tank, they will be seen swimming in that direction.
  • They are generally peaceful and will do well with other fish or even when they are more.

The only problem that you can have is when you keep them with similar species that can eat faster than they do. This will lead to starvation and possibly death if you do not separate them.

They will readily accept a wide range of food in the aquarium and they don’t know when to stop eating. You have to be careful when feeding them so that you will not overfeed them.

2. Paradise fish

paradise fish live in a freshwater tank
  • Paradise fish are a common freshwater fish that is native to East Asia.
  • Paradise fish are colorful and very attractive in an aquarium.
  • They have blue and black spots across their body and the females are usually identified by their smaller size.
  • It is also one of the most aggressive gourami species.
  • They are territorial and they may often fight especially if more than one male is kept together.
  • They will attack smaller fish that are kept in the same tank with them. Keep just one male with other females but keeping more than one male in the same tank is not advisable.
  • They usually won’t be aggressive unless they are the largest fish in the tank.
  • If they are with other fish that are larger than themselves, they will stay peaceful.
  • It is best to put them in a large tank, at least 20 gallons, and let it have vegetation to minimize their territorial behavior.
  • They have accessory breathing organs which means you can constantly see them coming to the surface to breathe air.

3. Koi

koi live in a freshwater tank

Another fish that can live in a freshwater tank is the koi. They are coldwater aquarium fish with patterns and distinct coloration on their body. Their color can range from blue to yellow, red, orange, black, or even white.

They are also members of the carp family just like goldfish but the main distinguishing feature between them and the goldfish is the babels on their lips.

Koi was a result of selective breeding done on the common carp because of its color. And if you want to keep your koi for a very long time you may need to have a large aquarium as they can grow bigger.

4. Green Sunfish

green sunfish live in a freshwater tank

The green sunfish is an aquarium fish of the sunfish family. This coldwater fish is native to North America and they can be easily identified by the yellow to green color found all over their body. They have a blue mark on their gills but they should not be confused with their close relative, the bluegills.

They are naturally territorial and therefore often become aggressive when placed with other fish. They can dominate other fish including their close relative such as the bigger bluegill.

They appear to make themselves bigger by opening their gill cover to scare other fish. They are very active and excited when you are feeding them.

5. Rosy Barb

rosy barb live in a freshwater tank

Barbs are common aquarium fish and the rosy barb will do well in a coldwater aquarium. They are pink in color but the male appears to be brighter and they also have a black color on their fins.

They are active in the aquarium, will live peacefully with other species and they are good for a community aquarium. Contrasting the background of the aquarium with black gravel will make its color more lively.

6. Rosy Red Minnow

rosy red minnow live in a freshwater tank
  • The rosy red minnow is a strain of the fathead minnow fish which is native to North America.
  • It is golden in color and it is sold as a coldwater aquarium fish.
  • They are active swimmers and can live together with other fish in the tank.
  • They are best kept in a school of 5-6 fish.

7. Rainbow Shiner

rainbow shiner live in a freshwater tank

Another cold-water fish species is the rainbow shiner.

  • This fish is translucent and the color is from pink to golden with a shiny silver-black appearance.
  • The base of its fins is reddish.
  • During the mating period, the male will usually change its color.
  • The region of the head may turn purple and the nostril may turn red while the ventral fin becomes blue.
  • They are hardy fish and they are not aggressive.

8. White Cloud Mountain Minnow

white cloud mountain minnow live in a freshwater tank

The white cloud mountain minnow is also called white cloud, white cloud mountain fish, or just white cloud minnow.

  • They are hardy fish and that makes them excellent for beginners without any experience.
  • The fish has a silver to green color with a red-colored caudal and dorsal fin.
  • There are different varieties of this fish and the color on them is used to differentiate them.
  • The male has a brighter color but they also have a smaller body.
  • The shape of the males’ dorsal fin is such that is wide apart while the female has a triangular fin shape.
  • They should not be kept alone as they will become timid and lose their bright coloration.
  • They should be kept in a school of at least 5 fish. They can live with other fish successfully but larger fish may eat them up.

9. Common Dace

common dace live in a freshwater tank

The common dace is a coldwater fish that belongs to the same family as the carp and they can survive at very low temperatures.

They are lively fish and don’t seem to be disturbed by the presence of other fish in the tank.

They have a silvery appearance and because of that, it is used as bait in sport fishing.

The head and part of the back have a dark coloration and the tips of the fins have colors ranging from white to black and red.

10. Clown Killifish

clown killifish live in a freshwater tank

Clown killifish is one of the most brightly colored coldwater aquarium fish. Killifish have a wide range of attractive colors. They are relatively peaceful however, the males will always fight each other.

One solution to this is to have a large tank with aquatic plants which will create a hiding place for the fish.

Warm Water or Tropical Fish Species

Warm water fish are fish that are native to the tropical region. You will usually have to heat the tank to maintain an optimum temperature for the growth of warm water fish.

There are different types of warm-water fish that are excellent choices for an aquarium.

1. Neon Tetra

neon tetra live in a freshwater tank

If you are just starting an aquarium for the first time, this is one of the recommended fish for you.

  • They are small and easy to take care of.
  • They will do well with other fish because they are not aggressive.
  • They prefer to be kept in a group rather than having just one in an aquarium.
  • Just like the neon light shines in the darkness, neon tetras are visible in the dark waters with their bright body colors.
  • They have a strip of horizontal blue color that runs across their body.
  • They are hardy and will readily accept most food that you present to them.
  • Some of their common foods however are worms and insects.

2. Guppies

guppies live in a freshwater tank

The guppies are well known as hardy warm water fish species that can survive in a variety of different water conditions.

They don’t require much to take care of them.

Guppies should be stocked at about 1 fish per gallon of water and they should be in the school of at least 3 fish.

The males of this fish are more brightly colored and if you don’t have any intention to breed them you can just maintain a male population.

They also accept a wide range of food that is plant-based and animal-based.

3. Oscar

oscar live in a freshwater tank

Another important tropical fish is the oscar.

  • They are not just attractive based on their colors but they are attractive based on their behavior too.
  • They are intelligent and can be taught to do a few tricks.
  • You can train them to feed directly from your fingers.
  • If you are planning to get a community aquarium, then an oscar is not a good candidate.
  • They prefer to be alone in the tank rather than living with other fish species.
  • The best practice is to add more than one fish in the tank to start growing together from a young age.

4. Mollies

mollies live in a freshwater tank

If you are looking for another warm-water fish that can survive in a variety of water conditions, then mollies are the best fish that should come to mind.

Mollies are small fish species that live peacefully with other fish in a freshwater tank.

They are omnivorous which means that they will take any food that is plant-based or animal-based.

You should start with a minimum tank size of 20 gallons if you want them to do well.

Another interesting thing about them is that they are prolific and multiply rapidly.

They are also live-bearers, meaning they don’t lay eggs but give birth to their young alive.

For a beginner, you may decide to keep single-sex if you don’t want to be overwhelmed with one more thing.

5. Zebra Danios

zebra danios live in a freshwater tank

Zebra danios is an excellent fish for those who are just starting.

  • They don’t require too much effort to start taking care of them.
  • You should start rearing this type of fish with at least a 10-gallon tank. Danios don’t like to be alone.
  • This means that if you add just a few danios into a tank then you are going to stress them out.
  • They live in a school and you must keep at least 5 of them for a start.
  • They will eat almost any food that you provide for them.
  • However, for their optimum growth, have their diet contain more worms and insects just like they do in their natural home.
  • A good quality feed should be enough to take care of them if you do not want to use insects and worms.
  • Make sure your tank is well covered because they are known to always make attempt to jump out of the tank.

6. Platies

platies live in a freshwater tank

If you can think of any color then there is probably a platy that looks just like that.

This fish not only comes in diverse colors but they are easy to take care of.

For these two reasons, they are a popular aquarium fish species that anyone can rear either as a beginner or an expert.

They are great community fish and will live together peacefully with molies and guppies.

They don’t like to be alone in a tank and they must be kept in a school of at least 5 fish.

They are omnivorous but they need more of the plant-based source of food than the animal-based source of food.

7. Cherry Barb

cherry barb live in a freshwater tank

The cherry barb is the name given to the species of barb whose male turn to a cherry-like color when it is spawning.

  • They are usually silver or black and they have a golden lateral line.
  • They are not aggressive fish and they will live peacefully with other fish.
  • They require at least a minimum of 25 gallons of a fish tank.
  • This will give them enough room to swim around and also the tank should have plants where they can hide if they feel threatened.
  • They don’t select food as they will pick almost any type of food that you feed them with.

8. Pearl Gourami

pearl gourami live in a freshwater tank

The pearl gourami is not an aggressive type of fish unlike some other species of gourami.

They can grow very large but they will remain peaceful and easy to keep. Because of their size, you should have a big tank with enough space.

It is recommended that you start with a minimum of a 30-gallon tank that has plenty of corners and low lighting area for the fish to hide.

They can be in a community of fish but they must be kept with other fish of similar size and tolerance.

You should not put them together with another very aggressive fish.

They are omnivorous fish and will eat almost any food that you provide for them.

9. Swordtails

swordtails live in a freshwater tank
  • The swordtail has a body shape that looks like that of the platies and guppies but it is bigger and has its fin extended as a sword.
  • They come in different colors, are hardy and that is one of the reasons why new hobbyists can start with a swordtail.
  • They are active swimmers and very lively fish.
  • They also do well in a community aquarium.
  • They can easily reproduce in the tank and if you want that to happen you have to separate the parents from the fry as they like to eat them.

10. Bettas

betas live in a freshwater tank

Betta is one of the most popular freshwater fish.

They are easy to care for and they also have a lively color.

Bettas can dwell together peacefully with other fish but the males can not be kept together.

Male bettas are known to always fight each other when they are kept in the same tank.

It is best to separate them and have just a single male per tank to avoid any form of fighting.

They are omnivorous fish and this means that they will eat food from any source given to them.

Conditions for Selecting Freshwater Fish

Now that you know the kind of fish that can live in a freshwater tank, it is also important to know the conditions that must be in place before selecting any fish for your aquarium. Not every fish will be good for you depending on what you want and the resources that you have available.

1. What is going to be the size of the fish at maturity? This will help you to match the type of fish that you want with the size of your aquarium if it will be able to hold it at maturity.

2. Can the fish live together with other types of fish? If you want a community aquarium, you have to do your research before buying one. Know the type of fish you want to buy and the temperament if it can live together with other fish.

3. Does the fish feed on live plants? Most herbivorous fish will feed on any live plant in the tank and make it look unattractive. If you are planning to have a live plant in your tank then you must know the type of fish you will add to avoid them feeding on it.

4. What is the water requirement of the fish? If you want to add a tropical fish to your tank then you need to know that you will need a heater to maintain the water temperature. Also, you need to know if the fish you want to put together have the same water quality requirement before bringing them together.


As you already know, an aquarium is not the natural home of a fish.

However, if you want your fish to survive then you must create a balanced environment that is similar to their natural habitat for them. It is difficult to always have a balance therefore you must engage in some management practices to keep the water condition optimum for the fish’s growth and wellbeing.

Most beginners think it is easier to maintain a smaller tank but when it comes to fish it is easier to maintain a larger tank. Big tanks have more water and less fluctuation of the water quality parameters.

Now that you know “What kind of fish can live in a freshwater tank” it’s time for you to have fun picking out which fish you want to fill your aquarium with. Have fun!

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Pet Aquariums

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