Tropical fish come in various sizes, colours, and patterns. If you combine the right species, you can create a vibrant tank that matches your dreams. Of course, we all know about guppies, mollies and swords, but what about the smaller ones with bursting colours meant for nano aquariums.
I have listed the most common small tropical fish into two sub-categories: fish for Nano tanks and fish for tanks over 10 gallons. This will help you in selecting the right fish for your aquarium setup.
22 Best tropical fish for small tanks
In my experience, when it comes to small tanks, there are two categories of tropical fish to consider: species suitable for nano tanks and those suitable for tanks starting at 10 gallons. So, I have gone on to list the species for you in those two categories; fingers crossed, it should help you with your choices for your fish tank.
Species for nano tanks
As a dedicated aquarist, I can confidently say that when it comes to stocking a nano tank, there are several freshwater Nano fish species that thrive in small spaces, and the most common of them are :
- Pygmy Corydoras
- Ember tetras
- Endler’s livebearers
- Harlequin rasboras
- Celestial Pearl Danios
- Chili rasboras
All of these fish can be kept in larger fish tanks but will do well in those if they are kept as larger family groups with no predatory species.
Pygmy Corydoras
The Pygmy Corydoras (Corydoras pygmaeus) is a small, peaceful fish native to South America. In my tank, they only grow up to 1 inch, making them perfect for nano tanks. Their docile nature and schooling behaviour ensure they make excellent tank mates with other non-aggressive species, further enhancing the visual appeal of your aquatic setup.
Ember tetra
The Ember Tetra (Hyphessobrycon amandae) is a captivating species from Brazil. Their fiery orange hue truly shone in my tank, making them a beautiful addition. They typically grow up to 2 centimetres, which makes them suited for nano tanks. These peaceful creatures prefer swimming in schools and can coexist harmoniously with other non-aggressive species, adding to the dynamic visual charm of your aquatic setting.
Endler’s
Endler’s livebearers (Poecilia wingei) are small, dynamic fish that hail from Venezuela. Their compact size of 1 inch (2.5cm) makes them ideal for nano tanks. This lively, hardy species is known for its vibrant bursts of colour, adding a visual spectacle to your tank. Peaceful by nature, they coexist harmoniously with other non-aggressive species in my fish tank, contributing to a balanced, vibrant nano aquarium community.
Harlequin rasbora
The Harlequin Rasbora (Trigonostigma heteromorpha) is a small, vibrant fish originating from Southeast Asia. Its maximum growth reaches 5 centimetres, making it an ideal fit for nano tanks. They’re known for their peaceable nature and schooling behaviour, ensuring a harmonious existence with other non-aggressive aquatic species. From what I noticed with mine, is that their distinctive colourful pattern enhances the visual appeal of any nano tank.
Celestial Pearl Danio
The Celestial Pearl Danio (Danio margaritatus) is a vibrant species native to Southeast Asia. With a maximum length of 1 inch (2.5cm), they’re a perfect fit for nano tanks. Their peaceful nature and preference for schooling make them excellent tank mates for other non-aggressive species. My fish used to have striking pearl-like spots and vivid colours, which made them well-suited to my small tank.
Chili Rasbora
The Chili Rasbora (Boraras brigittae), native to Indonesia, is a splendid addition to nano tanks, owing to its minute size of only 1.5 centimetres. Their warm, fiery hues add a touch of beauty to any aquatic display. Being a tranquil and schooling species, they coexist harmoniously with other non-aggressive species, contributing to the serene biodiversity of any nano tank environment.
Species for 10 gallon upwards
In my experience, some of the best tropical fish for small tanks that are 10 gallons or larger include:
- Guppy
- Neon tetra
- Zebra danio
- Betta Fish
- Cory catfish
- White Cloud Mountain minnow
- Cherry barb
- Cardinal tetra
- Common molly
- Swordtail
- Seluang fish
- Dwarf suckers
- Black Skirt Tetra
- Tiger barb
- Dwarf gourami
- Kuhli Loach
Some of these fish could also do well in nano tanks; however, they need to be just a few to ensure the fish have enough space to swim around, which is crucial for their development, lifespan and health overall.
Guppy
The Guppy (Poecilia reticulata), a native of South America, is renowned for its vibrant hues and dynamic energy. With a standard growth of 5 centimetres, Guppies are well-suited for smaller tanks. Their peaceful demeanour and schooling instinct made them ideal for cohabitation in my other non-aggressive species, contributing to a lively and colourful setup.
Neon tetra
The Neon Tetra (Paracheirodon innesi) is a visually striking choice from South America. They are ideal for smaller tanks with a maximum size of 3.5 centimetres in growth. They are peaceful schoolers who get along well with other non-aggressive species. Their vibrant, neon-blue and red stripes made them a stunning addition to my 20-gallon fish.
Zebra danio
I recommend keeping at least three Zebra danios (Danio rerio) together in a small tank, as they are known to thrive in groups. Zebra danios, also known as zebrafish, are popular for small tank fish enthusiasts. They are tropical fish that grow to about 2 inches (5cm) in size, making them perfect for nano tanks. These small, vibrant fish were highly active in my tank and will add a lively touch to any aquarium.
Betta Fish
The Betta Fish (Betta splendens), also referred to as the Siamese fighting fish, is a popular choice for smaller aquariums. Originating from Thailand, these hardy, beautiful fish grow up to 7 centimetres, making them suitable for smaller tanks. They are solitary by nature, and i kept them alone or with non-aggressive tank mates, and they seemed fine. With their striking appearance and flowing fins, Betta fish make visually appealing centrepieces for small aquatic setups.
Cory catfish
The Cory Catfish (Corydoras) from South America is a perfect addition to smaller aquariums. They fit well in smaller tanks with their modest size and tranquil nature, growing only up to 2.75 inches 7(cm). They have a peaceful temperament and can coexist harmoniously with other non-aggressive species. Their schooling instinct added to the visual charm of my aquatic setting. With their unique pattern and gentle behaviour, Cory Catfish enhance biodiversity and visual appeal in any small tank.
White Cloud Mountain minnow
White Cloud Mountain Minnow (Tanichthys albonubes) is a charming, peaceful fish hailing from the mountains of China. Their small stature, growing to a maximum of 4 centimetres, makes them an ideal inhabitant for smaller aquariums. In my tank, they exhibited schooling behaviour and coexisted comfortably with other non-aggressive species, contributing to a balanced and harmonious tank environment. Their vibrant silver bodies with dashes of red and blue add a splash of colour and visual interest to any small aquarium.
Cherry barb
The Cherry Barb (Puntius titteya), originating from Sri Lanka, is a perfect suit for smaller tanks due to its petite size, reaching only up to 2 inches (5cm). This peaceful species, known for its vibrant cherry red colour, cohabits amicably with other non-aggressive aquatic species. Their small stature and tranquil nature made Cherry Barbs a visually appealing and harmonious addition to my small tank community.
Cardinal tetra
The Cardinal Tetra (Paracheirodon axelrodi) is an enchanting freshwater species originating from South America. With their bright colors (blue and red stripes), these fish reach a maximum size of 2 inches (5cm), thus fitting smaller aquariums perfectly. Their peaceful nature makes them compatible with other non-aggressive species. The Cardinal Tetras in my tank are adept at forming schools, adding a dynamic and colourful feel to my aquarium.
Common molly
The Common Molly (Poecilia sphenops) is a versatile fish species from Central America. Growing up to 4.7 inches (12cm), Mollies are adaptable to different water conditions, making them suitable for smaller aquariums. I remember them best for their peaceful nature and excellent companions for non-aggressive species. Their variety of colours and attractive appearance will further add aesthetic value to your small tank.
Swordtail
The Swordtail (Xiphophorus hellerii) is a vibrant species from North and Central America, ideal for smaller aquariums due to its moderate size, reaching a maximum of 6.3 inches (15cm). Renowned for their peaceful temperament, the Swordtails in my tank made excellent tank mates for non-aggressive species. Their unique, elongated tail fin resembling a sword adds a fascinating visual element to a small or larger setup.
Seluang fish
The Seluang Fish (Rasbora sumatrana) is a small fish from Southeast Asia, growing only to a size of about 2.75 inches 7(cm). This petite size makes Seluang a superb candidate for smaller aquariums. Known for their peaceful demeanour, they are excellent tank mates for other non-aggressive species. The Seluang Fish is also a schooling species, adding an enticing dynamic to any small aquatic environment with their coordinated movement and vibrant colouring.
Dwarf suckers
The Dwarf Sucker (Otocinclus) is a small, serene fish species originating from South America. This fish grows to a maximum size of only 2 inches (5cm), making it a fitting choice for smaller aquariums. They add a unique aesthetic and dynamic element to any small tank, enhancing its visual appeal.
Black Skirt Tetra
The Black Skirt Tetra (Gymnocorymbus ternetzi) is a robust and visually compelling species from South America. Growing to a maximum of 2.75 inches 7(cm), they are well-suited to smaller aquariums. My memories about them are their peaceful nature and how well they got on with other non-aggressive aquarium fish, promoting a harmonious aquatic environment. Their dark colour and flowing fins added a dramatic touch to my small tank and enhanced its visual appeal.
Tiger barb
The Tiger Barb (Puntius tetrazona) is an incredibly active and eye-catching fish that brings a lively energy to any small tank. Their vibrant colours and distinctive stripes create a /visually stunning display. These small delights are perfect for smaller tanks, as they only grew to about 2 inches. They thrive in groups, so I kept at least 6 together to ensure their social behaviour flourishes in limited spaces. Overall, Tiger Barbs are an ideal species for compact aquariums.
Dwarf gourami
I often see Dwarf gouramis (Trichogaster lalius) recommended for small aquariums due to their small size and peaceful temperament. These vibrant fish are a great addition to any aquarium. Dwarf gouramis require a tank size of at least 10 gallons to thrive. In my setup, they were kept with other peaceful fish like tetras and rasboras. The unique colours and patterns of dwarf gouramis make them a visually striking choice.
Kuhli Loach
The Kuhli Loach (Pangio kuhlii) is a unique species originating from Southeast Asia. This small-sized creature, growing to a maximum of 10 centimetres, is perfect for smaller aquariums. Known for their peaceful nature, Kuhli Loaches in my fish tank made excellent companions for other peaceful fish. Their elongated, eel-like body and striking black and yellow stripes add a unique aesthetic touch, enhancing the visual diversity of any small tank.
After carefully researching and considering the best tropical fish for small tanks, it is clear that there are plenty of beautiful freshwater fish to choose from. These vibrant and stunning creatures can bring life and beauty to any small tank setup. From the lively and colourful guppies to the graceful and elegant bettas, a tropical fish will suit every aquarist’s preferences and tank size.
Frequently Asked Questions
Can Tropical fish thrive in small tanks?
- While keeping them in tanks smaller than 10 gallons is possible, there are challenges. Small tanks may not provide enough space for fish to swim and explore, and meeting the minimum requirements is crucial to avoid potential risks.
Are There Any Tropical Fish Species Suitable for Beginners With Limited Experience in Fishkeeping?
- Yes, there are many tropical fish species that are suitable for beginners with limited experience in fishkeeping. Some examples include fancy guppies, mollies, platies, and tetras, as they have easy care requirements and peaceful temperaments.
How Many Tropical Fish Can Be Safely Housed in a Small Tank Without Overcrowding?
- It’s important to consider the ideal tank size for tropical fish in a small tank and avoid overcrowding. To ensure success in your aquarium, you should use the rule of 1 gallon of water per fish (size-dependent).
Are There Any Tropical Fish Species That Are Known to Be Less Aggressive and More Peaceful for Community Tanks?
- Yes, there are several tropical fish species that are known for their peaceful nature and are suitable for community tanks. Some examples include mollies, platies, swordtails, gouramis, and rasboras.