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AquaManLife.com - Home-Bred Fish
AquaManLife.com - Home-Bred Fish

Top 25 Vibrant Nano Tank Fish for Small Freshwater Aquariums

Explore the top 25 vibrant nano tank fish for small freshwater aquariums! Add a burst of color and life to your compact aquatic space with these stunning species. Dive in and transform your aquarium today!

Nano tank fish

DEEP DIVE GUIDE - Discover the Science of Aquarium Filtration

Introducing the world of vibrant nano tank fish, perfect for adding a splash of colour to small freshwater aquariums! Whether you have a 5-gallon tank on your office desk or in child's room, a 10-gallon tank sitting proudly on your kitchen counter, or a trendy 29-30 gallon tank showcasing medium-sized species, we've got you covered.

 

Dive into our list of top 25 tiny, vibrant fish that will bring your nano aquarium to life and have you marveling at their beauty. Get ready to discover the incredible options available to transform your small aquatic haven into an underwater paradise!

Beautiful & Vibrant Freshwater Fish Perfect for Nano Tanks

Alright, let’s introduce you to 25 nano aquarium species that will make your aquarium pop. These vibrant fish are perfect for small spaces, and their care instructions are detailed below to help you provide the best environment for your new aquatic friends. Let’s dive in!

1. Danios

Scientific Name: Danio margaritatus

Origins: Myanmar and northern Thailand

Size: 1 in / 2.5 cm

Care Level: Moderate

Minimum Tank Size: 10 gal / 38 l

Temperature: 73-79°F / 23-26°C

pH Range: 6.5-7.5

Sexual Dimorphism: Celestial pearl danios exhibit some degree of sexual dimorphism. Males of the species are typically bright blue in color compared to a dull blue-green background seen in females. The fins of male fishes are more brightly colored as well, and the caudal peduncle is higher than a female’s. The bodies of both sexes are sprinkled with pearly white or light-yellow dots and the belly in females is yellowish white.

Lifespan: 3 to 5 years

Tank Setup:

  • Provide a densely planted aquarium with hiding spots and a gentle water flow.
  • Include driftwood and rocks for additional cover.
  • Use a sand or fine gravel substrate.

 

Diet:

  • Celestial Pearl Danios are omnivorous.
  • Feed them high-quality flake food, and supplement with live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

2. Chili Rasbora (Boraras)

Scientific Name: Boraras brigittae

Origins: Indonesia

Size: 0.8 in / 2 cm

Care Level: Easy

Minimum Tank Size: 5 gal / 19 l

Temperature: 68-82°F / 20-28°C

pH Range: 4.0-7.0

Sexual Dimorphism: In mature fish, males are often slightly more brightly coloured and the females are usually larger with rounder bellies.

Lifespan: 2 to 4 years

Tank Setup:

  • Provide a densely planted aquarium with hiding spots.
  • Use a sand or fine gravel substrate.
  • Add driftwood and leaf litter to mimic their natural habitat.

 

Diet:

  • Chili Rasboras are omnivorous.
  • Feed them high-quality flake food, and supplement with live or frozen foods like brine shrimp and daphnia.

 

Behavior & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

3. Gold Laser Corydoras (Dwarf Corydoras)

Scientific Name: Corydoras aeneus “Gold Laser”

Origins: Peru

Size: 2.5 in / 6 cm

Care Level: Easy

Minimum Tank Size: 20 gal / 75 l

Temperature: 72-79°F / 22-26°C

pH Range: 6.0-8.0

Sexual Dimorphism: Distinguishing male from female is a relatively easy process. Typically, females are larger and have a stockier body, especially when gravid, and possess rounder anal fins. The males are slimmer and have more pointed anal fin tips than the females.

Lifespan: Up to 5 years

Tank Setup:

  • Soft sandy substrate to prevent damage to their delicate barbels.
  • Provide hiding spots with rocks, driftwood, and plants.

 

Diet:

  • Omnivorous, feed them a mix of high-quality sinking pellets, live or frozen foods such as bloodworms, brine shrimp, and daphnia.

 

Behaviour & Compatibility:

  • Can be housed with other peaceful community fish of similar size.
  • Very peaceful and hardy addition to almost any aquarium  
  • Compatible with most adult dwarf shrimp and other invertebrates
  • Thrives in a group of at least 6
  • Distinctive coloration and group schooling behavior.
Kuhli Loach - Female
Kuhli Loach - Male
Kuhli Loach - Female

4. Kuhli Loach (Pangio kuhlii)

Scientific Name: Pangio kuhlii

Origins: Malaysia & Indonesia

Size: 4 in / 10 cm

Care Level: Easy

Minimum Tank Size: 20 gal / 76 l

Temperature: 75-86°F / 24-30°C

pH Range: 5.5-7.5

Sexual Dimorphism: Adult females are typically heavier-bodied and a little larger then males, while in mature males the first pectoral-fin ray is branched and thickened.

Lifespan: up to 14 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots, such as caves and driftwood.
  • Use a sand or fine gravel substrate for their comfort.
  • Maintain a gentle water flow and stable water parameters.

 

Diet:

  • Kuhli Loaches are omnivorous scavengers.
  • Feed them high-quality sinking pellets, flake food, and live or frozen foods like bloodworms and brine shrimp.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

5. Green Neon Tetra (Paracheirodon simulans)

Scientific Name: Paracheirodon simulans

Origins: Venezuela, Southeastern Colombia, Eastern Peru & Western Brazil

Size: 1.2 in / 3 cm

Care Level: Easy

Minimum Tank Size: 10 gal / 38 l

Temperature: 72-80°F / 22-27°C

pH Range: 5.0-7.0

Sexual Dimorphism: When determining sex, the best indicator is the relative sizes of the females and males. Males tend to be slightly smaller than females. Females also have a subtly more bulbous or rounded appearance.

Lifespan:  5-10 years

Tank Setup:

  • Provide a densely planted aquarium with hiding spots and a gentle water flow.
  • Use a dark substrate to bring out their vibrant colors.
  • Add driftwood and leaf litter to mimic their natural habitat.

 

Diet:

  • Green Neon Tetras are omnivorous.
  • Feed them high-quality flake food, and supplement with live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

6. Clown Killifish (Banded Panchax)

Scientific Name: Epiplatys annulatus

Origins: West Africa

Size: 1.4 in / 3.5 cm

Care Level: Moderate

Minimum Tank Size: 10 gal / 38 l

Temperature: 72-78°F / 22-25°C

pH Range: 6.0-7.5

Sexual Dimorphism: Males are more colourful, develop more-extended fins and grow larger than females.

Lifespan: 2 to 3 years

Tank Setup:

  • Provide a densely planted aquarium with hiding spots, such as floating plants and driftwood.
  • Use a sand or fine gravel substrate.
  • Maintain a gentle water flow and stable water parameters.

 

Diet:

  • Clown Killifish are primarily carnivorous.
  • Feed them a diet of small live or frozen foods, such as brine shrimp, daphnia, and mosquito larvae.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

7. Ember Tetra (Hyphessobrycon amandae)

Scientific Name: Hyphessobrycon amandae

Origins: Native to the Araguaia River basin of Brazil

Size: 0.8 in / 2 cm

Care Level: Easy

Minimum Tank Size: 10 gal / 38 l

Temperature: 68-82°F / 20-28°C

pH Range: 5.5-7.0

Sexual Dimorphism: Adult males are more intensely-coloured, especially when in spawning condition, while females are noticeably rounder-bodied.

Lifespan: 2 to 4 years

Tank Setup:

  • Provide a densely planted aquarium with hiding spots and a gentle water flow.
  • Use a dark substrate to bring out their vibrant colors.
  • Add driftwood and leaf litter to mimic their natural habitat.

 

Diet:

  • Ember Tetras are omnivorous.
  • Feed them high-quality flake food, and supplement with live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.
Panda Guppy - Males
Panda Guppy - Female

8. Panda Guppy (Poecilia reticulata)

Scientific Name: Poecilia reticulata

Origins: South America

Size: 2.4 in / 6 cm

Care Level: Easy

Minimum Tank Size: 5 gal / 19 l

Temperature: 64-82°F / 18-28°C

pH Range: 6.8-7.8

Sexual Dimorphism: Males generally exhibit more vibrant and bold colors, with a longer and narrower anal fin that is specially modified for mating. Females, on the other hand, are typically larger in size and have a less intense coloration than males.

Lifespan: Around 2 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots for their fry.
  • Use a gentle water flow and maintain good water quality.
  • Add a sponge filter to protect their offspring.

 

Diet:

  • Panda Guppies are omnivorous.
  • Feed them high-quality flake food, spirulina, and live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

9. Blue Eye Rainbowfish (Pseudomugil gertrudae)

These guys come in several different colour varieties, most of them being vibrant.

Scientific Name: Pseudomugil gertrudae

Origins: Papua New Guinea and Northern Australia

Size: 1.4 in / 3.5 cm

Care Level: Moderate

Minimum Tank Size: 10 gal / 38 l

Temperature: 72-79°F / 22-26°C

pH Range: 6.0-8.0

Sexual Dimorphism: Females are characterized by a deeper body structure, while the males possess larger dorsal, pelvic, and anal fins with elongated filaments on the first dorsal and pelvic fins.

Lifespan: 3 to 5 years

Tank Setup:

  • Provide a densely planted aquarium with hiding spots and a gentle water flow.
  • Use a sand or fine gravel substrate.
  • Maintain good water quality.

 

Diet:

  • Spotted Blue Eye Rainbowfish are omnivorous.
  • Feed them high-quality flake food, and supplement with live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.
Spotted Blue Eye Rainbowfish
Furcata Blue Eye Rainbowfish

10. Hillstream Loach ( Sewellia lineolata)

These guys may not be a super vibrant fish, but their golden tone is still just as beautiful. For me, the best part is how they remind me of a miniature stingray! They also have nice little personalities.

Scientific Name: Sewellia lineolata

Origins: Vietnam and Laos

Size: 2.5 in / 6 cm

Care Level: Moderate

Minimum Tank Size: 20 gal / 75 l

Temperature: 68-75°F / 20-24°C

pH Range: 6.5-7.5

Sexual Dimorphism: Females plumper than males. Males have raised areas like small “fences” on first few rays of pectoral fins, and when viewed from above are noticeably “squarer” in the area of the front leading edge of the pectoral fins. (See pictures below). Care: Inhabit fast flowing streams over boulders.

Lifespan: 5 to 10 years

Tank Setup:

  • Fast-flowing water to mimic their natural habitat.
  • Provide smooth rocks and caves for hiding and resting spots.
  • Use a powerful filter for proper water movement and aeration.

 

Diet:

  • Omnivorous, primarily algae grazers; supplement with high-quality sinking pellets, algae wafers, and blanched vegetables like spinach or zucchini.

 

Behaviour & Compatibility:

  • Peaceful and best kept in groups of at least 5 to encourage natural behavior.
  • Can be housed with other peaceful, fast-moving fish that thrive in high water flow conditions. Avoid slow-moving or long-finned fish, as they may struggle in the strong current.

11. Harlequin Rasbora

Scientific Name: Trigonostigma heteromorpha

Origins: Malaysia, Singapore, Sumatra and southern Thailand.

Size: 1.8 in / 4.5 cm

Care Level: Easy

Minimum Tank Size: 10 gal / 38 l

Temperature: 72-81°F / 22-27°C

pH Range: 5.0-7.5

Sexual Dimorphism: The process of identifying the gender of Harlequin Rasbora is relatively straightforward. Males tend to have more striking colours and a slimmer physique than their female counterparts. In addition, the triangular patch on the male’s body is typically rounder and more elongated than in females. On the other hand, females tend to have a plumper body shape and less distinct colouration compared to males.

Lifespan: 5 to 8 years

Tank Setup:

  • Provide a densely planted aquarium with hiding spots and a gentle water flow.
  • Use a dark substrate to bring out their vibrant colors.
  • Add driftwood and leaf litter to mimic their natural habitat.

 

Diet:

  • Harlequin Rasboras are omnivorous.
  • Feed them high-quality flake food, and supplement with live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

12. Otocinclus (Dwarf Suckers)

Scientific Name: Otocinclus spp.

Origins: Peru

Size: 2 in / 5 cm

Care Level: Moderate

Minimum Tank Size: 10 gal / 38 l

Temperature: 72-82°F / 22-28°C

pH Range: 6.0-7.5

Sexual Dimorphism: Otocinclus exhibits very prominent sexual dimorphism. Upon reaching reproductive age, the females become much larger and wider than the males. Their sex organs are also distinctively different. Females have larger and more vibrant sex organs.

Males have genital papilla with several rows of odontoid (modified denticles.) These organs are visible at the side of the tail system. This organ helps orient the Otocinclus male fish during the breeding process. 

Lifespan: 3 to 5 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots, such as driftwood and caves.
  • Use a sand or fine gravel substrate.
  • Maintain a gentle water flow and stable water parameters.

 

Diet:

  • Otocinclus are primarily herbivorous.
  • Feed them high-quality sinking pellets, algae wafers, and blanched vegetables.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

13. Emperor Tetra

Scientific Name: Nematobrycon palmeri

Origins: San Juan and Atrato River basins in Colombia, South America

Size: 1.5 in / 4 cm

Care Level: Easy

Minimum Tank Size: 20 gal / 75 l

Temperature: 73-82°F / 23-28°C

pH Range: 6.0-7.5

Sexual Dimorphism: Males tend to be slightly larger and more colorful, with an extended central ray in their caudal fin and a blue-black stripe running along their body. Females are generally smaller, less colorful, and have a shorter and rounder caudal fin. The black stripe in females is less pronounced and may even appear broken in some specimens.

Lifespan: 3 to 6 years

Tank Setup:

  • Planted tank with ample swimming space.
  • Provide driftwood, rocks, and hiding spots for the fish.
  • A dark substrate can help bring out their colors.

 

Diet:

  • Omnivorous; feed a varied diet of high-quality flakes or pellets, frozen or live foods such as daphnia, brine shrimp, and bloodworms.

 

Behaviour & Compatibility:

  • Peaceful, schooling fish; keep in groups of at least 6 to encourage natural behavior and reduce stress.
  • Can be housed with other small, peaceful community fish like tetras, rasboras, and dwarf cichlids. Avoid aggressive or fin-nipping species.

14. Bumblebee Goby

Scientific Name: Brachygobius spp.

Origins: Indonesia, Malaysia and Brunei

Size: 1.2 in / 3 cm

Care Level: Moderate

Minimum Tank Size: 5 gal / 19 l

Temperature: 72-82°F / 22-28°C

pH Range: 6.8-8.5

Sexual Dimorphism: Distinguishing between male and female Bumblebee Gobies is generally straightforward. Males typically exhibit a slimmer body and more vibrant colors, often displaying an orange hue instead of yellow. Conversely, females tend to have a fuller physique and may possess smaller, rounder heads.

Lifespan: around 3 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots, such as caves and driftwood.
  • Use a sand or fine gravel substrate.
  • Maintain a gentle water flow and stable water parameters.

 

Diet:

  • Bumblebee Gobies are primarily carnivorous.
  • Feed them a diet of small live or frozen foods, such as brine shrimp, daphnia, and bloodworms.

 

Behaviour & Compatibility:

  • They can be territorial; it is best to keep them in a species-only tank or with small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

15. Scarlet Badis (Dario dario)

Scientific Name: Dario dario

Origins: Tributaries of the Brahmaputra River system in the Indian states of Assam and West Bengal (close to the border with Bhutan).

Size: 0.8 in / 2 cm

Care Level: Moderate

Minimum Tank Size: 5 gal / 19 l

Temperature: 68-78°F / 20-25°C

pH Range: 6.5-7.5

Sexual Dimorphism: Females are smaller, less colourful (they do not have any red or blue pigmentation on the flanks and only indistinct bars or none at all) and possess a noticeably shorter, stumpier-looking body profile then males. In addition, males develop extended pelvic, dorsal and anal fins as they mature.

Lifespan: 4 to 6 years in captivity

Tank Setup:

  • Provide a densely planted aquarium with hiding spots, such as rocks and driftwood.
  • Use a sand or fine gravel substrate.
  • Maintain a gentle water flow and stable water parameters.

 

Diet:

  • Scarlet Badis are primarily carnivorous.
  • Feed them a diet of small live or frozen foods, such as brine shrimp, daphnia, and bloodworms.

 

Behaviour & Compatibility:

  • They can be territorial; it is best to keep them in a species-only tank or with small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

16. Neon Tetra

Scientific Name: Paracheirodon innesi

Origins: Native to blackwater and clearwater streams in the Amazon basin of South America

Size: 1.2 in / 3 cm

Care Level: Easy

Minimum Tank Size: 10 gal / 38 l

Temperature: 68-80°F / 20-27°C

pH Range: 6.0-7.0

Sexual Dimorphism: The male is slender, and the blue line is straighter. The female is rounder, producing a bent blue line. Some aquarists say the females look plumper when viewed from above. However, the straightness of the line and the plumpness of the female might occasionally be due to the eggs she is carrying.

Lifespan: They can have a lifespan of as long as ten years, but normally just two to three years in an aquarium.

Tank Setup:

  • Provide a densely planted aquarium with hiding spots and a gentle water flow.
  • Use a dark substrate to bring out their vibrant colors.
  • Add driftwood and leaf litter to mimic their natural habitat.

 

Diet:

  • Neon Tetras are omnivorous.
  • Feed them high-quality flake food, and supplement with live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

17. Betta Fish

Scientific Name: Betta splendens

Origins: Southeast Asia

Size: 2.5-3 in / 6-7.5 cm

Care Level: Easy

Minimum Tank Size: 5 gal / 19 l

Temperature: 76-82°F / 24-28°C

pH Range: 6.0-7.5

Sexual Dimorphism: Males have long ventral and tail fins with vivid and uniform body coloration, whereas females have shorter fins and dull, patterned bodies. Further, the males exhibit an aggressive nature.

Lifespan: 3 to 5 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots, such as caves and driftwood.
  • Use a gentle water flow and maintain good water quality.
  • Add a heater to maintain a stable temperature.

 

Diet:

  • Betta Fish are primarily carnivorous.
  • Feed them high-quality pellets or flakes, and supplement with live or frozen foods like brine shrimp and bloodworms.

 

Behaviour & Compatibility:

  • Males are aggressive toward each other; do not keep them together.
  • They can be kept with small, non-aggressive fish, but they may nip at the fins of long-finned species.

18. Cardinal Tetra

Scientific Name: Paracheirodon axelrodi

Origins: Upper Orinoco and Negro Rivers in South America

Size: 2 in / 5 cm

Care Level: Moderate

Minimum Tank Size: 10 gal / 38 l

Temperature: 73-81°F / 23-27°C

pH Range: 4.0-7.0

Sexual Dimorphism: There is very little sexual dimorphism among cardinal tetras, with the main difference being size. Females are usually slightly larger than males. Females are a bit larger, which allows them to hold more eggs. This is especially important if you plan on breeding them.

Lifespan: Around five years on average when raised in captivity. Some lucky fish can even reach ten years of age when properly taken care of. They have much shorter life spans in the wild, only living to about a year or so. Conversely, the Neon Tetra has a shorter life in captivity than in the wilderness.

Tank Setup:

  • Provide a densely planted aquarium with hiding spots and a gentle water flow.
  • Use a dark substrate to bring out their vibrant colors.
  • Add driftwood and leaf litter to mimic their natural habitat.

 

Diet:

  • Cardinal Tetras are omnivorous.
  • Feed them high-quality flake food, and supplement with live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

Scientific Name: Poecilia reticulata

Origins: South America

Size: 2.4 in / 6 cm

Care Level: Easy

Minimum Tank Size: 5 gal / 19 l

Temperature: 64-82°F / 18-28°C

pH Range: 6.8-7.8

Sexual Dimorphism: Female guppies grow throughout their life, whereas males slow down their growth during maturation. Male and female guppies also display behavioral differences in the amount of time spent mating, foraging, shoaling, and avoiding predators.

Lifespan: 2 to 5 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots for their fry.
  • Use a gentle water flow and maintain good water quality.
  • Add a sponge filter to protect their offspring.

 

Diet:

  • Fancy Guppies are omnivorous.
  • Feed them high-quality flake food, spirulina, and live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.
Blue Moscow Guppy

20. Asian Stone Catfish

Not extremely bright in colouration, but beautiful patterns and very interesting looking fish to say the least!

Scientific Name: Hara jerdoni

Origins: Sluggish streams of India and Bangladesh

Size: 1.4 in / 3.5 cm

Care Level: Moderate

Minimum Tank Size: 10 gal / 38 l

Temperature: 68-77°F / 20-25°C

pH Range: 6.0-7.5

Sexual Dimorphism: Unknown. It is likely that females will appear broader than males when full of eggs.

Lifespan: About 5 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots, such as rocks and driftwood.
  • Use a sand or fine gravel substrate.
  • Maintain a gentle water flow and stable water parameters.

 

Diet:

  • Asian Stone Catfish are primarily carnivorous.
  • Feed them a diet of small live or frozen foods, such as brine shrimp, daphnia, and bloodworms.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

21. Endler Guppy

Scientific Name: Poecilia wingei

Origins: Paria Peninsula in Venezuela

Size: 1.4 in / 3.5 cm

Care Level: Easy

Minimum Tank Size: 5 gal / 19 l

Temperature: 72-80°F / 22-27°C

pH Range: 6.7-8.5

Sexual Dimorphism: Males aren’t larger than 1 inch (2–2,5 cm), female fish can grow up to 1.4 inches long (3,5 cm). The female fish coloring is sole-colored with golden or silvery tint. Behind its abdomen, there is a small spot, which indicates that they have some embryos inside.

Lifespan: 2 to 3 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots for their fry.
  • Use a gentle water flow and maintain good water quality.
  • Add a sponge filter to protect their offspring.

 

Diet:

  • Endler’s Livebearers are omnivorous.
  • Feed them high-quality flake food, spirulina, and live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.
Endler Guppy
Japan Blue Endler
Japan Blue Endler
Sparkling Gourami

22. Sparkling Gourami

Scientific Name: Trichopsis pumila

Origins: Southeast Asia

Size: 1.6 in / 4 cm

Care Level: Easy

Minimum Tank Size: 5 gal / 19 l

Temperature: 72-81°F / 22-27°C

pH Range: 6.0-7.5

Sexual Dimorphism: Can be tricky to sex, but sexually mature males are normally exhibit a more intense colour pattern and develop longer ventral, anal, dorsal, and caudal fins than females.

Lifespan: 4 to 5 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots, such as floating plants and driftwood.
  • Use a gentle water flow and maintain good water quality.
  • Keep the tank covered, as they can jump out.

 

Diet:

  • Sparkling Gouramis are omnivorous.
  • Feed them high-quality flake food, spirulina, and live or frozen foods like brine shrimp and daphnia.

 

Behaviour & Compatibility:

  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

23. Dwarf Pencilfish

They come in many different colour variations, some of them being quite vibrant.

Scientific Name: Nannostomus marginatus

Origins: Guyana and Suriname and parts of the Amazon basin in Peru, Colombia, and Brazil

Size: 1.6 in / 4 cm

Care Level: Easy

Minimum Tank Size: 10 gal / 38 l

Temperature: 74-81°F / 23-27°C

pH Range: 5.5-7.5

Sexual Dimorphism: Males exhibit a more slender physique and more intense coloration compared to females. Additionally, some males have a modified anal fin with the third to sixth rays being widened, further aiding in differentiation.

Lifespan: Maximum of 5 years usually

Tank Setup:

  • Provide a well-planted aquarium with floating plants to create a shaded area.
  • Use a gentle water flow and maintain stable water parameters.
  • Keep the tank covered, as they can jump out.

 

Diet:

  • Dwarf Pencilfish are primarily carnivorous.
  • Feed them a diet of small live or frozen foods, such as brine shrimp, daphnia, and bloodworms.

 

Behaviour & Compatibility:

  • They are a surface-dwelling schooling fish so keeping them in groups of around 6 is best
  • Peaceful fish suitable for community tanks with other small, non-aggressive fish.
  • Avoid keeping them with larger or more aggressive species.

Now I know they’re not an actually fish, however they are beautifully bright in colour and really are a great addition to any small tank so I decided to include them in this list. Bonus side to them is they help in keeping your tank nice and tidy!

Scientific Name: Neocaridina davidi

Size: 1.2 in / 3 cm

Care Level: Easy

Minimum Tank Size: 5 gal / 19 l

Temperature: 65-85°F / 18-29°C

pH Range: 6.5-8.0

Tank Setup:

  • Provide a well-planted aquarium with hiding spots, such as rocks, driftwood, and moss.
  • Use a sponge filter to protect their offspring.
  • Maintain good water quality and stable water parameters.

 

Diet:

  • Cherry Shrimp are omnivorous.
  • Feed them high-quality shrimp pellets, algae wafers, and blanched vegetables like zucchini, spinach, and cucumber.

 

Behaviour & Compatibility:

  • Cherry Shrimp are peaceful and can be kept in a community tank with small, non-aggressive fish.
  • Avoid keeping them with larger or aggressive fish that might eat them.

25. Pea Puffer

Scientific Name: Carinotetraodon travancoricus

Origins: Western Ghats of India

Size: 1 in / 2.5 cm

Care Level: Moderate

Minimum Tank Size: 5 gal / 19 l

Temperature: 72-82°F / 22-28°C

pH Range: 6.8-7.8

Sexual Dimorphism: Sexual dimorphism is apparent in mature fish, with males being more brightly coloured than females and having a yellow ventral surface. Males can also have a dark stripe down the centre of their pale belly and iridescent, blue “eye wrinkle” patterns that females do not have.

Lifespan: Around 3 years

Tank Setup:

  • Provide a well-planted aquarium with hiding spots, such as rocks, caves, and driftwood.
  • Use a gentle water flow and maintain good water quality.
  • Keep the tank covered, as they can jump out.

 

Diet:

  • Pea Puffers are primarily carnivorous.
  • Feed them a diet of live or frozen foods, such as brine shrimp, daphnia, and bloodworms.
  • They also eat small snails, which help to keep their beaks trimmed.

 

Behaviour & Compatibility:

  • Pea Puffers can be aggressive and territorial, especially towards their own kind.
  • They are best kept in a species-only tank or with small, fast-moving, non-aggressive fish.
  • Avoid keeping them with slow-moving or long-finned fish, as they may nip at their fins.

I decided I would add a couple extra bonus species here for you as well. They are personal favourites of ours, and if you have the right sized nano tank fish, then they are a perfect choice!

ANCISTRUS/BRISTLENOSE PLECOS

You can find Bristlenose Plecos for sale in our shop – Super Red Bristlenose & Blue Eyed Lemon Bristlenose

Scientific Name: Ancistrus sp.

Origins: Amazon River basins in South America

Size: 4-6 in / 10-15 cm

Care Level: Easy

Minimum Tank Size: 25 gal / 95 l

Temperature: 60-80°F / 15-27°C

pH Range: 6.5-7.5

Sexual Dimorphism: The location and length of their tentacles; the tentacles of
males are found on top of the snout and are larger than those of females and juveniles which are located only along the snout margin.

Lifespan: 10-15 years if looked after correctly and kept healthy.

Tank Setup:

  • Provide hiding spots like caves, rocks, and driftwood.
  • Make sure there’s a strong filtration system as they produce a lot of waste.

 

Diet:

  • Omnivorous, they eat algae, vegetables, and sinking pellets.

 

Behaviour & Compatibility:

  • Peaceful, they can be kept with other non-aggressive fish.

Scientific Name: Pseudotropheus saulosi

Origins: Lake Malawi in East Africa

Size: 3-4 in / 7.5-10 cm

Care Level: Moderate

Minimum Tank Size: 30 gal / 114 l

Temperature: 75-82°F / 24-28°C

pH Range: 7.8-8.6

Sexual Dimorphism: The dominant male has an intense blue color with dark blue vertical bars, while females and young fish are yellow, which makes them one of the nicest cichlids to have with even the juveniles being colourful from the beginning, and the females not being dull in colour.

Lifespan: About 5 years

Tank Setup:

  • Provide a sandy substrate with lots of rocks and hiding spots.
  • Make sure the water is well-oxygenated.

 

Diet:

  • Omnivorous, feed them a variety of high-quality pellets, flakes, and live/frozen food.

 

Behaviour & Compatibility:

  • Can be aggressive, especially during breeding; they’re best kept in a species-only tank.
Male and Female Cichlid Saulosi

Final Thoughts

Phew, you did it!

These 25 colorful freshwater nano tank fish are perfect for small aquariums, offering vibrant colors, interesting behaviors, and manageable care requirements. From livebearers like guppies to schooling fish like neon tetras, there is a species to suit every aquarist’s preferences. Just remember to provide the appropriate care, including a suitable tank size, proper water parameters, and a balanced diet to ensure your colourful nano fish thrive.

Quick Overview

Fish SpeciesScientific NameSize (in/cm)Care LevelMinimum Tank Size (gal/l)Temperature (°F/°C)pH Range
Danio (Celestial Pearl Danio)Danio margaritatus1″/2.5cmModerate10 gal/38 litres73°F-79°F/23°C-26°C6.5-7.5
Chili RasboraBoraras brigittae0.8″/2cmEasy5 gal/19 litres68°F-82°F/20°C-28°C4.0-7.0
Gold Laser CorydorasCorydoras sp.1.4″/3.5cmEasy20 gal/76 litres72°F-78°F/22°C-25°C6.0-8.0
Kuhli LoachPangio kuhlii4″/10cmEasy20 gal/76 litres75°F-86°F/24°C-30°C5.5-7.5
Green Neon TetraParacheirodon simulans1.2″/3cmEasy10 gal/38 litres72°F-80°F/22°C-27°C5.0-7.0
Clown KillifishEpiplatys annulatus1.4″/3.5cmModerate10 gal/38 litres72°F-78°F/22°C-25°C6.0-7.5
Ember TetraHyphessobrycon amandae0.8″/2cmEasy10 gal/38 litres68°F-82°F/20°C-28°C5.5-7.0
Panda GuppyPoecilia reticulata2.4″/6cmEasy5 gal/19 litres72°F-82°F/22°C-28°C6.8-7.8
Blue Eye RainbowfishPseudomugil gertrudae1.2″/3cmModerate10 gal/38 litres72°F-79°F/22°C-26°C6.5-8.0
Hillstream LoachBeaufortia kweichowensis2.4″/6cmModerate20 gal/76 litres68°F-75°F/20°C-24°C6.5-7.5
Harlequin RasboraTrigonostigma heteromorpha1.8″/4.5cmEasy10 gal/38 litres72°F-81°F/22°C-27°C6.0-7.0
OtocinclusOtocinclus sp.2″/5cmModerate10 gal/38 litres72°F-79°F/22°C-26°C6.0-7.5
Emperor TetraNematobrycon palmeri2″/5cmEasy20 gal/76 litres73°F-82°F/23°C-28°C6.0-7.5

FAQs

What is a nano tank and what makes it different from regular aquariums?

A nano tank is a small aquarium, typically 10 gallons or less, designed to house small aquatic species. They’re perfect for small spaces and require less maintenance than larger tanks.

Can I keep multiple fish species together in a nano tank?

Yes, you can keep multiple species together in a nano tank, as long as they have similar requirements and are compatible with each other. Research each species’ needs and compatibility before adding them to your tank.

How do I maintain the water quality in a nano tank?

Perform regular water changes, monitor water parameters, and maintain a suitable filter. Good water quality is essential for the health of your fish and other aquatic inhabitants.

How many fish can I keep in a nano tank?

The number of fish you can keep depends on the size of your tank and the specific needs of each species. As a general rule, allow 1 gallon of water per 1 inch of fish, but always research each species’ requirements.

Can I keep plants in a nano tank?

Yes, you can grow live plants in a nano tank. Plants help maintain water quality and provide shelter for fish. Choose plants that are suitable for small tanks, such as Anubias and Java Moss.

Do nano tank fish require a heater?

Some nano tank fish species require a heater to maintain a stable temperature, while others do not. Research the temperature requirements of your chosen fish species before setting up your tank.

What type of filtration is best for a nano tank?

A small, efficient filter, such as a sponge filter or hang-on-back filter, works well for nano tanks. Choose a filter with adjustable flow rates to avoid strong currents that may stress your fish.

How do I acclimate fish to my nano tank?

Slowly acclimate fish to the new tank conditions by floating their bag in the tank for 15-20 minutes, then gradually mixing tank water into the bag over the next 30 minutes. This helps fish adjust to the new temperature and water parameters.

Can I breed fish in a nano tank?

Some small fish species, like guppies and cherry shrimp, can breed in nano tanks. Research the breeding requirements of your chosen species and provide the necessary conditions for successful breeding.

How do I prevent disease outbreaks in my nano tank?

Maintain good water quality, avoid overstocking, and quarantine new fish before adding them to the main tank. Regularly observe your fish for signs of illness and act quickly if you notice any symptoms.

How often should I clean my nano tank?

Perform partial water changes (20-30%) every 1-2 weeks, and clean the filter, substrate, and decorations as needed. Regular maintenance will keep your nano tank clean and healthy for its inhabitants.

Example Site - Nano Tank Frequently Asked Questions(FAQ)

If you have any other further questions about anything aquatic related, please do not hesitate to contact us right away! Stay tuned – we will be starting to load incredibly helpful and useful videos on the AquaManLife.com YouTube channel and Facebook page, so keep a look for that coming!