10 Best Small Aquarium Fish For Nano Tank: Care Requirements & Fun Facts!

Small nano tanks are growing in popularity because they are affordable, easy to care for, and don’t take up a lot of space. But what kind of fish can you put in them?

If you’re looking for some of the best small aquarium fish perfect for nano tanks, you’ve come to the right place. 

This article will look at 10 of the best small aquarium fish great for smaller tanks. These fish are easy to care for and make great additions to any home aquarium.

I’ll also describe their care requirements so you can make sure your tank is set up correctly. 

With the right information, keeping a small nano tank can be a lot of fun and very rewarding. 

So what are you waiting for? Start exploring the best small aquarium fish ideal for nano tanks today!

Best small aquarium fish for nano tanks

In the best small aquarium fish list, I tried to keep different types of fish species so that you can enjoy the diversity of their character. 

I’ve added some bottom feeders, algae eaters, centerpiece fish, schooling fish, etc., to help you set up your tank with the best possible combination. 

Bottom feeders and algae eaters will help you clean the leftover foods, fish wastes, and algae. Therefore, your tank will remain clean and have healthy water parameters. 

Because of their presence, nuisance staffs like worms can’t develop & maintenance frequency will be lowered. Try to keep a fish combination that croupy all three layers of water in your aquarium. 

So, let’s jump into the characteristics and care requirement sections for small aquarium fish.

1. Celestial Pearl Danio

Celestial Pearl Danios

Celestial Pearl Danios are schooling fish that come from the family Cyprinidae. These fish are very active and playful and make great additions to any home aquarium.

There is sexual dimorphism in color, with males being more beautiful than females. Males have a bright blue background with lustrous golden pearls scattered everywhere compared to the dull grayish-brown females. And their fins are made up of an orange and black combination.

Celestial Pearl Danios are easy to care for but a bit shy. Therefore, it is essential to make them feel safer by increasing the size of their group and providing plenty of decorations. 

Fortunately, they grow only about 1-inch long, making them an ideal candidate for a small tank. However, they should be kept in schools of six or more. 

They prefer a water temperature between 73 and 79 degrees Fahrenheit and a pH level of around neutral. However, they are pretty flexible with the water conditions.

They also prefer feeding midwater, not at the top or bottom, so you should use this fact to favor your pet’s happiness! They can be provided with a variety of foods, including flakes, pellets, freeze-dried food, and live food.

Celestial Pearl Danios can peacefully reside with other non-hostile community fish like neon tetra, Corydoras, or even bettas. 

2. Chili Rasbora

Chili Rasbora

Chili Rasbora is a lively, small schooling fish from Southeast Asia. They are about .75 inches long and have a reddish color with black markings that look like chili peppers.

You can find primarily juveniles at the fish store that is much paler in appearance. But, if you bring them home and take good care of them, their coloration will blossom six months down the line!

They are very active and playful, making them fun to watch in an aquarium. However, they do best when kept in schools of six or more, and they prefer a water temperature between 68 and 78 degrees Fahrenheit and a pH of 5-7.

Because of their small size, try to bring at least 10 Chili Rasbora. Also, make sure they have plenty of plants around for shade because this will make your tank feel complete with life.

Like other fish in this list, they are easy to care for and can be fed various foods, including flakes, pellets, brine shrimp, and Daphnia.

3. Cory Catfish (Corydoras)

Cory Catfish

Cory catfish are bottom-feeder fish; they are effortless to keep, entertaining, and one of the best fish for beginners. They come in various colors and can grow up to be about two inches long.

The Corry Catfish is a schooling fish, and it appears to be happier in a group of two or more, and they also get along with other fish. They are also easy to breed, if you like breeding it’s the perfect choice to keep.

Cory Catfish will care for you by working as a scavenger in your tank. They utilize food found in the lowest areas of the water column to survive.

However, the floating pallet may never reach them; you can feed them some sinking algae wafers or pallets to ensure proper nutrition.

Their optimum temperature is 72 to 80 degrees Fahrenheit. However, they can tolerate a wide range of temperatures, including temperatures cooler than tropical.

The Corry Catfish, like other catfish, can breathe oxygen from the atmosphere, which is why they occasionally move to the top of the tank to take in air. Read the complete care guide for cory catfish here.

4. Ember Tetra

Ember Tetra

The bright orange-red body of the Ember tetra will make your aquarium pop, and they are best suited for tanks with plants.

They can survive in water temperatures of 75 to 82 degrees Fahrenheit, and their size can range from one-half inch to three-quarters of an inch long.

The best way to feed them is by providing them with small pallets that contain protein, vitamins, and other nutrients. They are best kept in groups of six or more fish.

They should be fed a small amount two to three times per day. Ember tetra eagerly eats from all levels of the aquarium.

They are peaceful community fish and get along well with other inhabitants. However, I don’t recommend significantly larger fish than the Ember Tetra as the tank mate because, accidentally, they may snack on them. 

Cory catfish, Chili Rasbora, and Neon tetras are compatible with the Ember Tetra. 

5. Neon Tetras

Neon Tetra

Neon Tetras are best known as “schooling fish.” Schooling fish like to be in groups of five or more. Most schooling fish do best with 15-20+ of their own species; Neon tetras are no exception to this rule.

A fascinating thing about neon tetra is it changes colors! While sleeping at night, neon tetra’s blue or red colors become gray or black and reactivate when it becomes awake.

They prefer warmer water, so a temperature between 73 and 81 degrees Fahrenheit is best for them. They can withstand a temperature as low as 70 degrees Fahrenheit, but they will not thrive in cooler water temperatures.

They are very small fish, only growing to be about an inch long. Neon tetras can easily fit in the palm of your hand. Because of their small size and timid nature, they are best kept with other smaller fish that inhabit the upper and lower areas of the aquarium.

Fish that would make good tank mates for Neon Tetras are Cory catfish, Ember tetras, Guppies, Platys, and Swordtails.

Neon Tetra love to stay in the middle part of the water. Therefore, they should be fed high-quality flake food or pellet designed for small fish. You can also supplement their diet with freeze-dried bloodworms, tubifex, or brine shrimp.

6. Betta Splenden (Siamese Fighting Fish)


Betta Splendens, also known as the Siamese fighting fish, is a beautiful and popular aquarium fish. They are best kept in single-sex pairs (male/female). However, they can be housed in groups if only females are present (With Caution). Read more about the betta sorority here.  

They come in many different colors, including blue, green, red, and yellow. They also have many different types of fins, including short and long fins. Bettas are tough fish because of their ability to survive in low-oxygen environments through their “labyrinth organs.”

Bettas grow to a length of 2.25 inches on average; depending on how well they are cared for, they can also reach 3 inches. Bettas are best kept in tanks between ten gallons to twenty gallons. 

If you opt for a smaller tank, make sure it is heated properly, and the water is changed regularly. The bigger the tank, the better it is for Bettas.

Read More: Top Seven Fish Tanks for Betta Fish (Awesome & Fascinating)

They prefer moderate light levels but can tolerate low light conditions if required. They thrive best in temperatures between 78 to 82 degrees Fahrenheit.

They are best suited for tanks that have plants, as it gives them a place to hide and places to evade other fish. Their diets can consist of flakes, pellets, and live foods such as bloodworms or brine shrimp. Know more about betta fish here.

7. Otocinclus Catfish

Otocinclus Catfish

Otocinclus Catfish are best known as little algae eaters, but they are more than that. They are best kept in groups of three or more fish because they don’t do well alone.

They prefer cooler water temperatures between 70 to 80 degrees Fahrenheit and thrive best in moderate light conditions.

Otocinclus Catfish prefers slow-moving water with rocks, driftwood, and plants. They like to stay at the bottom area of the tank.

Feed them algae wafers or blanched vegetables like zucchini, spinach leaves, and cucumber once a day. You can also supplement their diet with live foods such as bloodworms and brine shrimp.

They will only eat algae if they are hungry, so supplement their diet with food to ensure that your Otocinclus Catfish is getting enough nutrients.

Otocinclus Catfish can grow up to two inches in length but stay small for most of their lives. As a result, they best thrive in tanks between ten gallons and twenty-five gallons; this gives them plenty of space to swim and explore.

8. Guppies


Guppies are livebearers, meaning that they give birth to live young. Guppies come in many different colors and fin types, making them popular for aquariums.

They are best kept in groups of five or more fish. They prefer water temperatures between 73 and 82 degrees Fahrenheit and thrive best in moderate light conditions.

The best plants for guppy fish are floating plants, such as duckweed or water lettuce because they provide a place for the fry to hide from adult fish that may eat them.

Guppies best thrive in tanks between ten gallons and twenty-five gallons; this gives them plenty of space to swim and explore and adds beauty to your aquarium.

Feed guppies various foods, including flake food, algae wafers, and frozen or live brine shrimp.

9. Zebra Danios

Zebra Danios

Zebra Danios are best known as beginner fish because they are inexpensive and easy to care for. They are also very active and make a great addition to any tank.

They are pretty-looking fish and come in various colors, including blue, black, and silver. In addition, zebra pattern stripes are present on their bodies, which vary in color.

Zebra Danios needs a tank at least 20 gallons in size, with plenty of live plants and rocks for hiding.

They do best when kept in schools of six or more fish. The water temperature should be maintained between 68 and 75 degrees Fahrenheit.

Zebra Danios are compatible with other community fish, such as Neon Tetra, Chili Rasbora, etc.

10. Dwarf Gourami

Dwarf Gouramis

Dwarf Gourami is a beautiful fish that comes in many colors, including blue, red, and orange. They have a long, thin body with vertical stripes running along the length of their body.

They are best kept in pairs or groups of three because they do not do well when alone. They prefer water temperatures between 76 to 82 degrees Fahrenheit and thrive best in moderate light conditions.

Dwarf Gourami best thrive in tanks between ten gallons and twenty-five gallons; this gives them plenty of space to swim and explore and adds beauty to your aquarium.

Feed them a variety of foods, including flake food, algae wafers, and frozen or live brine shrimp

Wrapping Up

When it comes to the best small aquarium fish, there are many options available in terms of size and type. This list should help you choose the best fish for your tank!

Each of these fish has its own unique set of care requirements, so be sure to do your research before adding any new fish to your tank.

If you have any questions or want to share your own experiences keeping nano tank fish, please comment below.

I love getting feedback and hearing about people’s successes (and failures) with fishkeeping. Happy fishkeeping!

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Sujit Modak

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