15 Popular Small Freshwater Fish for Nano Tanks (Ultimate Guide)

Adorable Small Freshwater Fish
By Subhash Das Updated

Fish hobbyists love petting aquatic species but many of them have a very small space in their apartments, which is the main reason that they quit the idea of keeping fish or bringing a large beautiful aquarium because it will require substantial space. If you are one of them then why don’t you act smart and bring some small freshwater fish breeds and keep them in a nano tank at home or office?

It is quite obvious if you buy 1-2” (2.54-5.08 cm) fish breeds since then you will hardly need 5-10 gallons aquarium for them to dwell. Therefore, be smart to fulfil your wish and include some cute and small freshwater fish in your little aquatic family.

Cute Little Fish for Small Tanks

No need to ignore your hobby of fishkeeping if you have a 1 or 2 BHK apartment or a petite-space in your home. You can still pet your favorite fish in small aquariums that are available in shops nowadays. We have listed the names of some small-sized fish that you can easily keep in a little aquarium or fishbowl.

01

Dwarf Puffer

Dwarf Puffer Fish

Quick Details

  • Size: 1” (2.54 cm)
  • Tank Size: 5 gallons
  • Diet: Carnivoros
  • Temperament: Semi-Aggressive
  • Care Level: Moderate
  • Color: Brown, Yellow, White

Fish enthusiasts are attracted to this fish because of its bright yellowish or brown color and shiny blue eyes. You can easily bring a 5-gallon nano tank for this 1” (2.54 cm) small freshwater fish because it never grows much in wild and captive. Moreover, Dwarf puffer can dwell in various types of water conditions whether it is freshwater or saltwater. So, don’t you find this aquatic species interesting? You can keep this yellowish fish both in freshwater and marine water tanks because of its adaptable nature.

If you are planning to keep more than one Pufferfish then it will be better if you bring a 10-gallon aquarium. Pufferfish loves greenery, so it will be comfortable if you set a green leafy environment by keeping aquatic plants in its aquarium. You can also keep shrimps and snails in the water house of Dwarf Puffer as it is a carnivoros species and consumes meaty foods.

02

Betta Fish

Betta Fish

Quick Details

  • Size: 3” (7.62 cm)
  • Tank Size: 5 gallons
  • Diet: Carnivoros
  • Temperament: Peaceful
  • Care Level: Easy
  • Color: Dark Blue, Copper, Red, Brown, Green, Orange, etc.

This popular freshwater fish is found in most of the aquariums of beginners and experienced fishkeepers because of its vibrant colors, aesthetic patterns and beautiful fins which are admirable. Moreover, fish hobbyists just need a small 5-gallon tank to keep this passive-natured little fish because Betta fish is flexible in nature and it can adjust in various kinds of water conditions.

Never keep this notorious jumper fish in a small bowl because they jump high and try to come out of the tank. Moreover, Bettas are active swimmers, so they cannot swim well in a small round bowl; a rectangular-shaped aquarium is perfect for Betta fish. You can also keep a good heater in the tank, as this small freshwater fish enjoys the warm water.

03

Celestial Pearl Danios

Celestial Pearl Danios

Quick Details

  • Size: 1” (2.54 cm)
  • Tank Size: 5 gallons
  • Diet: Omnivoros
  • Temperament: Peaceful
  • Care Level: Easy
  • Color: White Spots on Red, Orange and Bluish Body with Red Fins  

You can keep a single Celestial Pearl Danio (CPD) in a small 5-gallon fish tank, but these small freshwater fish are schooling fish and they prefer living with a shoal. Therefore, purchase a 10-gallon aquarium to keep a shoal of Danios.

The striking vibrant shades, beautiful pattern, peaceful nature and small size of this freshwater fish makes it the best choice for both beginners and experienced aquarists. You can feed all types of meaty and vegetative foods to this omnivoros fish. Danio is not a picky eater, so it enjoys live foods, dried foods, and pellets.

04

Sparkling Gourami

Sparkling Gourami

Quick Details

  • Size: 1” (2.54 cm)
  • Tank Size: 5-10 gallons
  • Diet: Omnivoros
  • Temperament: Peaceful
  • Care Level: Easy
  • Color: Bluish, Gray, Green, Brown, etc.

Another name of Sparkling Gourami is Pygmy Gourami which is the smallest fish in Gourami family famous for its bright and shimmering shades. Like Danios, Sparkling Gouramis are also schooling fish which likes living in a shoal. So, you can keep 4-5 small Gouramis in a 10-gallon aquarium. This small freshwater fish just needs a 5-gallon tank if kept alone.

Gouramis prefer dwelling in a natural environment, so try to keep live plants, driftwoods, and caves in the aquarium of Sparkling Gourami. Also, feed both herbs and meaty foods to this omnivoros fish which will help them increase their brightness.

05

Bumblebee Goby

Bumblebee Goby

Quick Details

  • Size:1” (2.54 cm)
  • Tank Size: 5 gallons
  • Diet: Carnivoros  
  • Temperament: Semi-Aggressive
  • Care Level: Difficult  
  • Color: Pale Yellow with Orange Bands  

Similar to Dwarf Puffer, Bumblebee Goby is also comfortable to live in freshwater and brackish water. So, you can keep this 1.5” (3.81 cm) fish in any type of water. Although it is a small species, it is territorial in nature, so you should only keep them with other gobies and small species. You can keep a single Goby fish in a 5-gallon aquarium and a shoal in a 10-gallon aquarium.

06

Endler’s Livebearers

Endler’s Livebearers

Quick Details

  • Size: 1” (2.54 cm)
  • Tank Size: 5-10 gallons
  • Diet: Omnivoros
  • Temperament: Peaceful
  • Care Level: Easy
  • Color: Metallic Green, Orange, Black, etc.

This small freshwater fish is famous for its vibrant psychedelic patterns. This livebearer fish develops its eggs in its womb and gives birth to live fries. Moreover, Endler’s Livebearer breeds regularly, so it will be a good decision if you purchase a 10-gallon aquarium for this fish and its cute little fries.

You can set a low maintenance tank for keeping this small fish because of its hardy and resilient nature. This omnivoros fish is peaceful and adjustable, so it is easy to take care of this breed by both novice and expert fishkeepers.

07

Norman’s Lampeye Killifish

Norman's Lampeye Killifish

Quick Details

  • Size: 1.5” (3.81 cm)
  • Tank Size: 5-10 gallons
  • Diet: Carnivoros
  • Temperament: Peaceful
  • Care Level: Easy
  • Color: Creamy, Light Brown

If you have small space and nano aquarium in your home then Norman’s Lampeye Killifish is one of the best choices. Famous for the resilient and peaceful nature, this fish is totally different from other species of Killifish family.

You can keep about 3-5 fish in a 10-gallon aquarium. Try to keep some floating plants, small rocks, and caves in the tank of this little shy-natured fish.

08

Ember Tetra

Ember Tetra

Quick Details

  • Size: 1” (2.54)
  • Tank Size: 10 gallons
  • Diet: Omnivoros
  • Temperament: Peaceful
  • Care Level: Easy
  • Color: Bright Red and Bright Orange

Ember Tetra is a Brazilian freshwater fish that prefers living in slow water where thick vegetation is found. You will generally find this small freshwater fish at the bottom of the water, so you need to keep small rocks, caves, and thick plants like Java Fern and Anacharis in the bottom of the tank for their comfort.

Not only for its miniature size, but fish enthusiasts love keeping this fish for its striking features and beautiful colors.

09

Least Killifish

Least Killifish

Quick Details

  • Size: 1.5” (3.81 cm) 
  • Tank Size: 3 gallons  
  • Diet: Omnivoros
  • Temperament: Peaceful 
  • Care Level: Easy 
  • Color: Yellow, Light Orange, Straw-Shaded, etc.  

The smallest tropical fish of North America, Least Killifish is another peaceful peace in the family of Killies. This tiny fish does not lay eggs; it is a livebearer which directly gives birth to little fries. This 1.5” (3.81 cm) fish is a slow swimmer, so it is comfortable to live in a 3-gallon aquarium.

Least Killifish does not need any special kind of water temperature because it is comfortable in various types of water conditions, which is one of the prime reasons that fish hobbyists prefer keeping this species in their aquarium.

10

Endler’s Guppy  

Endler’s Guppy

Quick Details

  • Size: 1.8” (4.57 cm)     
  • Tank Size: 5 gallons    
  • Diet: Omnivoros  
  • Temperament: Peaceful 
  • Care Level: Easy  
  • Color: Metallic Green, Black, and Orange    

Usually, Guppies are suitable members of a nano tank, and Endler’s Guppy is the smallest fish in the Guppy family. They are one of the popular algae eaters, so it is the main reason that fishkeepers chose them for their aquarium. Moreover, this 1.8” fish just needs a 5-gallon aquarium to dwell comfortably.

This fish is both familiar and fearless, so it is social to other small tankmates also. Endler’s Guppy prefers living in warm water, so it will be better if you set a mild warm tank for this small freshwater fish.

11

Pygmy Corydoras

Pygmy Corydoras

Quick Details

  • Size: 1.3” (3.30 cm)   
  • Tank Size: 10 gallons
  • Diet: Omnivoros  
  • Temperament: Peaceful 
  • Care Level: Easy
  • Color: Silver

Active and friendly, this little fish is passive and social with other peaceful-natured water species. This 1.3” (3.30 cm) non-aggressive fish is relatively easy to keep because you just need a 10-gallon aquarium for this species.

This mid-dwelling fish looks attractive because of its silver shades and black streak patterns. Just try to keep them with small peaceful fish because it is uncomfortable to live with large predators.

12

Scarlet Badis

Scarlet Badis

Quick Details

  • Size: 0.78” (2 cm)    
  • Tank Size: 5-10 gallons   
  • Diet: Omnivoros    
  • Temperament: Peaceful (Aggressive towards fellow males)  
  • Care Level: Intermediate 
  • Color: Bright Red, Rusty Orange, Silvery Gray 

If you are planning to keep a nano aquarium in your home then collect small freshwater fish like 0.78” (2 cm) Scarlet Badis in your aquatic pet home. Although the female fish are smaller than the male, they are sometimes aggressive towards their fellow males. So, while planning to set a tank, avoid keeping male and female Badis together.

You should adorn the tank of this bright red-colored fish with natural lighting, floating plants, small rocks and plenty of caves for them to hide from their enemies.

13

Hara Jerdoni

Hara Jerdoni

Quick Details

  • Size: 1.2” (3 cm)      
  • Tank Size: 10 gallons     
  • Diet: Omnivoros     
  • Temperament: Peaceful    
  • Care Level: Easy  
  • Color: Light Brown, Gray, Dark Brown Reddish Brown with Mottling Dark Band or Patches   

Originated from India, Hara Jerdoni is one of the tiniest members in Catfish family that is found in rivers, small streams, and ponds. This bottom-dwelling whiskered fish lives inactive at the bottom of the tank, so it is known as Stone Fish also. It is a good algae eater or tank cleaner, so fish hobbyists keep it in their aquarium.

Above-average oxygen level in the tank is ideal for Hara Jerdoni because they are bottom dwellers. This nocturnal fish consumes live worms, shrimps and frozen or dried foods.

14

Neon Tetra

Neon Tetra

Quick Details

  • Size: 1.5” (4 cm)        
  • Tank Size: 10 gallons       
  • Diet: Omnivoros      
  • Temperament: Peaceful     
  • Care Level: Easy
  • Color: Blue, Red, Bicolor, and Translucent 

If you are a beginner aquarist and are looking for small peaceful fish for your nano fish tank then Neon Tetra is the ideal choice for you. Not only small in size but its shimmering color and adaptable nature makes it the best fish for a beginner’s aquarium.

This mid-level fish is hardy, active and social. It is not a picky eater, so that is an extra benefit to keep this easy-to-care fish. However, don’t get confused between Cardinal Tetra and Neon Tetra because both are similar in color but dissimilar in size. Neon Tetra is small and Cardinal Tetra is the larger of the two.

15

Salt and Pepper Catfish

Salt and Pepper Catfish

Quick Details

  • Size: 0.75” (2 cm)
  • Tank Size: 10 gallons
  • Diet: Omnivoros
  • Temperament: Peaceful     
  • Care Level: Easy
  • Color: White with Black Bands

This South American tropical fish is found in shallow water and small streams. This is a schooling fish, so it enjoys swimming with a school of fish. However, you would not require much space for this species; a 10-gallon aquarium is perfect to keep a shoal of Salt and Pepper Catfish.

This fish has black and white colors and patterns on its body, so it is known as Salt and Pepper Catfish. It is also a good algae eater like Hara Jerdoni and it prefers living at the bottom of the fish tank.

Things Required to Set a Nano Fish Tank

Long we have discussed the small freshwater fish, now let’s acquire ideas about the necessary things to set a small tank.

  • Nano Aquarium
  • Filtration System
  • Lighting
  • Live Freshwater Plants
  • Fine Gravels
  • Caves or Hiding Places

How to Set Up and Maintain a Nano Tank for Small Freshwater Fish?

You will get various aquariums in the market but it is not easy to choose the right fish tank for your little swimmer buddies because a proper home is necessary for the cute little aquatic species. Therefore, look after some requirements while setting a fish tank.

1. Aquarium with Lighting (2-in-1)

Buy a mini aquarium of 3-gallon like Marine Land Contour Glass Aquarium Kit with Rail Light. You will get this aquarium with light settings on the top of the tank. So, you don’t need to buy an extra light for your pet fish.

You can also buy a 5-gallon tank, Fluval Spec V Aquarium Kit. Not only an aquarium but it is available with LED light and bio rings.

2. Filtration System

People have a wrong belief that small fish tanks do not need filters. The filtration system is actually needed to kill bacteria of the water and wash out the toxic elements from the tank. For a 5-gallon aquarium, Deep Blue Professional Nano Filter is an ideal choice that helps in washing out the toxins and wastes.

3. Ornamentation of Fish Tank

Usually, a fish comes from a natural habitat of river and stream, so it is quite obvious that it prefers living in a natural ambience. So, no matter if your aquarium is small or not, you can keep small ornaments to delight your little aquatic buddies.

You can keep small fine gravels at the bottom of the tank so that the small species can take rest. Setting one small cave will help a fish hide or lay eggs in it.

Lastly, keep 1-2 floating freshwater plants like Java Fern or Duckweed for making the ambience of the fish world eco-friendly and natural because fish enjoys the greenery.

4. Maintenance

We have discussed on the setting of the tank, now, let’s discuss the cleanliness and hygiene management. Yes, you need to manage the aforesaid things and also the water temperature of the tank for each species but keeping the fish home clean is one of the major factors which is needed to be maintained primarily.

Clean up the tank with mild liquid soap, soft brush, and aerated water. After cleaning, wipe out the tank and the objects. Moreover, change about 10-15% of the water every week to maintain the water condition because your fish cannot dwell in a polluted water condition.

Bottom Line

After lots of information about the small freshwater fish and the nano tank set-up for them, don’t you think fishkeeping can be the best hobby even if you have a small apartment and less space? Why not? You can easily follow the above-mentioned ideas to pet the cute little companions of your choice.

Learn More about Popular Fish Breeds

We have discussed small fish for nano aquariums, so if you want to learn further about other popular fish then read these topics: