Beginners Guide to 21 Small Freshwater Fish for Small Aquariums

A tiny ray-finned fish for tiny aquariums
Golden yellow bodies with dark green or brown stripes. Slight reddish to orange tinge near the eyes.
A bright black and orange horizontal exclamation running along the center of their bodies on both sides, ending with a black dot mark towards the tail differentiates them from the rest
Diet – Omnivore

A tropical small fish, which is most desirable. Its entire body glows under dark light.
It has a radiant light blue or electric blue body
A distinct shinier blue line in the center runs from the nose to the start of its tail
Its impeccable beauty is further enhanced by a bright red broad line running through the lower belly till the start of its tail
Active, playful schooling fish. Fun to add
Diet – Omnivore

A live bearing tropical small fish from the Guppy species
An active shoaling fish that gives birth to frys instead of laying eggs (livebearer)
A bright fusion of colors adorns them. Tails are transparent fan-like with a bold colored outline on the sides (full or partial)
Bodies have a combination of colors like silver, green, orange, red, black, and blue, with random patterns making them desirable
Diet – Omnivore

An unorthodox addition to small aquariums
Natural tank cleaners + create very less bioload of their own
They have worm-shaped bodies with small fins and whiskers on their mouths. Contrast asymmetrical stripes cover their shiny to dull skins in various colors
Diet – Omnivore, Scavengers
Read here for more details

This small fish is added for algae control and considered to be good tank cleaners
Active shoaling fish
Their mouth acts like suction to suck algae from surfaces. They have very small teeth and two whiskers in their mouths
A horizontal stripe (brown or black) runs across their body from the head to the beginning of the tails. The pattern varies and is slightly smokey
Diet – Omnivore

A beautiful small schooling fish for small aquariums
Ensure the tank lid is closed, as they are jumpers
It is rocket-shaped from broad tail to tapering slender body to its mouth and fins in sides
Contrast colored horizontal stripes cover its silver/light brown body. The tail is multi-colored. The body has a fusion of colors like silver, black, blue, golden yellow, red, green, brown, randomly
Diet – Omnivore, Prefer live foods

A tiny schooling fish from the Japanese paddy fields has gained ground among hobbyists due to its simple yet elegant appearance

A study suggests that these fish has developed face recognition skills like humans, helping them recognize faces of its species. They fail to recognize inverted faces

There is a blue ring around its eyes, whereas the body is creamish white to creamish yellow in color

Its scales shimmer in the dark, giving it an irresistible glow. There is a slight bluish tinge on its lower body

A vibrant small freshwater shoaling fish for small aquariums

Their bodies are honey-yellow in color giving them a glow of sunset colors

Narrow body with a small increasing (in height) threadlike sequence of anal and dorsal fins and semi-transparent fan-shaped tail makes it picture perfect for your aquarium

Amicable
4 to 8 years

2 to 3
Mid to Top-Level

A striking small schooling fish for hobbyists and experts alike

Males have shining cherry red bodies with a dark line contouring their lower bodies. Females are light cherry to peach in color, with a darker hue on the upper bodies

A black central horizontal line runs from their mouths to the start of their forked tails

4 (20 gallons tank only)
Top to Mid-Level

A freshwater schooling fish apt for small tank

It has a shining brown body with a bluish-green hue on the upper portion.

A black and pinkish fluorescent center line runs from its mouth to the start of the tail and ends with a semicircular black mark

This black semi-circle has an orange tinge around it, covering its transparent tail partially

Its mouth is slightly upwards with a protruding lower jaw

5 to 20
Middle to Top-Level

A popular small  shoaling fish for fish lovers

Shades of copper, pink, orange, silver, red and yellow ooze out on its body randomly. The eyes have a golden circle around them. The forked transparent tail also displays a fusion of colors

A black triangle (almost 90 degrees) commencing a little below its dorsal fin and tapering to the start of the tail, is its distinguishing feature

Harmonious
5 to 8 years

One of the cutest small freshwater schooling fish in the hobby-circle

Its body is off-white to pink to creamish.

Instead of scales, it has small bony plates on its body. These thin plates meet at the center of the body from top and bottom, forming a continuous sequential pattern

Three black marks – first on the eye (like a panda), second at the start of the dorsal fin, and third at the start of the tail – are its distinguishing feature

Peaceful
8 to 10 years

4 to 6
Top to Mid-Level

A striking small schooling freshwater fish suited for small aquariums

They have a vibrant translucent greenish body with a neon blue central line running from its mouth to the start of the tail

It has a broad red mark from its lower belly to the start of the tail. Fins and tail are transparent

Diet – Omnivore

Calm
2 to 3 years

6 to 10
Middle and Top-Level

A gorgeous small schooling fish for a small aquarium

It has a striking contrast caused by its body colors. Its body is semi-transparent green, with a bright black central line running from its mouth to the start of the tail. The fins and tail are transparent

There is a half-red circle around the top of its eye. The balance circle has varying colors like yellow, green, black, or a combination of these

Non-Aggressive
3 to 5 years

Mid to Top-Level