Characins

Explore all characins in our database. Browse detailed care guides, compatibility information, and species data to find the perfect fish for your aquarium.

Showing 1 - 24 of 51 Fish Profiles

African Pike

Hepsetus odoe

Characins

30 cm Aggressive

The African Pike is a formidable and fascinating predatory fish native to West and Central Africa. With its elongated, torpedo-shaped body and a mouth full of prominent sharp teeth, it is a surface-dwelling ambush predator that requires a massive aquarium. Best kept by advanced aquarists, they are heavily piscivorous and will consume any fish that fits in their mouths, though they are generally tolerant of similarly sized, robust tank mates.

Banded Leporinus

Leporinus fasciatus

Characins

30 cm Aggressive

A large, striking, cigar-shaped characin native to the Amazon Basin, recognized by its bold black and yellow bands. While beautiful, they are notoriously active, prone to jumping, and infamous for systematically destroying live plants. They grow quite large and can be semi-aggressive, particularly toward their own kind or fish with long fins.

Beckford's Pencilfish

Nannostomus beckfordi

Characins

6.5 cm Peaceful

A peaceful, slender schooling fish native to the sluggish rivers and swamps of South America. They are famous for the males' harmless but spectacular lateral sparring displays. They require heavily planted aquariums with gentle flow and make excellent tank mates for other peaceful, soft-water species. A tight-fitting lid is essential as they are known to be proficient jumpers.

Bentos Tetra

Hyphessobrycon bentosi

Characins

4.5 cm Peaceful

A striking, deep-bodied tetra native to the slow-moving waters of the Amazon basin. Characterized by a reddish-brown tint and a prominent black spot on the dorsal fin, often tipped with white. They are active but peaceful schooling fish. Males will frequently engage in harmless, visually impressive sparring displays to establish hierarchy and impress females.

Black Neon Tetra

Hyphessobrycon herbertaxelrodi

Characins

4 cm Peaceful

A peaceful, active schooling fish native to the Paraguay basin. Known for its striking contrast of a dark black lateral stripe underneath a glowing iridescent white/green-gold stripe. Excellent for community aquariums, particularly in planted setups or blackwater biotope tanks with subdued lighting.

Black Pacu

Colossoma macropomum

Characins

90 cm Mostly Peaceful

The Black Pacu (Tambaqui) is a massive, incredibly fast-growing Amazonian fish. Closely related to Piranhas, they possess crushing, human-like teeth evolved for cracking nuts and seeds. Due to their enormous adult size (often exceeding 3 feet and 60 lbs) and extreme bioload, they are completely unsuitable for standard home aquariums and require colossal custom tanks or heated indoor ponds.

Black Phantom Tetra

Hyphessobrycon megalopterus

Characins

4.5 cm Peaceful

A peaceful, deep-bodied schooling tetra native to the Guaporé and Paraguay river basins. They are named for the distinct 'phantom' black patch behind their gills. They thrive in heavily planted tanks with subdued lighting (often achieved via floating plants or blackwater conditions). Males engage in spectacular but harmless 'mock battles' where they flare their fins at each other.

Black Skirt Tetra

Gymnocorymbus ternetzi

Characins

7 cm Mostly Peaceful

A very hardy, deep-bodied schooling tetra native to South America. They are incredibly popular for beginners but have a reputation as fin-nippers if kept in too small a group. A proper school disperses their internal bickering and largely prevents them from harassing other tank mates.

Bleeding Heart Tetra

Hyphessobrycon erythrostigma

Characins

7 cm Peaceful

A relatively large, deep-bodied tetra known for the distinctive bright red spot on its flank resembling a bleeding heart. They are active schoolers that require plenty of swimming space. While generally peaceful, they can become fin-nippers if kept in numbers fewer than 6 or in an undersized aquarium.

Blind Cave Tetra

Astyanax mexicanus

Characins

10 cm Mostly Peaceful

A fascinating, totally blind species originating from limestone caves in Mexico. They are born with eyes that degenerate as they grow. Navigating via their highly sensitive lateral line, they are extremely active and constantly scavenge for food. Best kept in a species tank or with fast-moving, short-finned fish, as their erratic swimming and feeding style can result in accidental fin-nipping of slow tank mates.

Bloodfin Tetra

Aphyocharax anisitsi

Characins

5.5 cm Peaceful

An extremely hardy and energetic schooling fish characterized by its silver body and striking bright red fins. As exceptionally active swimmers, they require plenty of horizontal swimming space. They are very adaptable to temperature and water parameters, making them a fantastic choice for beginners. Must be kept in groups to curb minor fin-nipping tendencies.

Blue Emperor Tetra

Inpaichthys kerri

Characins

4 cm Peaceful

The Blue Emperor Tetra, also known as the Royal Tetra, is a stunning, active schooling fish native to the Aripuanã River basin in Brazil. They feature a bold dark lateral stripe and vibrant blue-purple iridescence that intensifies in planted aquariums with slightly acidic water. Males will actively spar and display to establish dominance, but are harmless to other species.

Blue Tetra

Knodus borki

Characins

5 cm Semi-Aggressive

A strikingly beautiful but notoriously boisterous schooling fish. Often misidentified in the trade as Boehlkea fredcochui. Known for their intense iridescent blue coloration, they are incredibly fast, hyperactive swimmers. They are infamous fin-nippers and require a long tank and a large group (8+) to prevent them from terrorizing slower or long-finned tank mates.

Brilliant Rummy-Nose Tetra

Hemigrammus bleheri

Characins

5 cm Peaceful

One of the tightest schooling fish in the aquarium hobby, known for their striking bright red faces and black-and-white horizontally striped tail fins. They are highly active and need plenty of horizontal swimming space. The intensity of their red 'nose' serves as an excellent biological indicator of water quality and stress; it fades significantly if water parameters drop or they feel insecure.

Bucktooth Tetra (Exodon)

Exodon paradoxus

Characins

12 cm Highly Aggressive

The Bucktooth Tetra is a highly active, predatory shoaling fish infamous for its scale-eating (lepidophagous) behavior. They are extremely aggressive and will strip the scales, fins, and even eyes off almost any tankmate. They must be kept in a species-only tank in large groups (12+) to disperse their intense conspecific aggression; otherwise, they will systematically kill each other.

Buenos Aires Tetra

Hyphessobrycon anisitsi

Characins

7 cm Semi-Aggressive

A large, incredibly hardy, and highly active tetra from South America. While they are nearly bulletproof regarding water parameters and great for beginners, they are notorious fin-nippers and voracious plant eaters. They must be kept in larger schools to disperse internal aggression and housed with equally robust, fast-moving tank mates (like larger Barbs or robust Catfish). Do not keep with long-finned fish, slow swimmers, or in delicate aquascapes.

Cardinal Tetra

Paracheirodon axelrodi

Characins

4 cm Peaceful

A stunning schooling fish native to the upper Orinoco and Rio Negro basins in South America. Famous for its brilliant iridescent blue line and a vivid red stripe that extends the full length of its body (distinguishing it from the Neon Tetra). They are strictly schooling fish that thrive in warm, acidic blackwater environments.

Colombian Tetra

Hyphessobrycon columbianus

Characins

7 cm Mostly Peaceful

A larger, deep-bodied tetra known for its striking metallic blue body and bright red fins. They are very active and can be somewhat boisterous. They are known to occasionally nip fins if kept in groups that are too small or in tanks that lack adequate swimming space.

Congo Tetra

Phenacogrammus interruptus

Characins

8.5 cm Peaceful

A stunning, large schooling fish native to the Congo River basin. Known for their iridescent rainbow colors and active swimming behavior. Despite their size, they are notoriously peaceful and can be skittish, requiring ample swimming space, dim lighting or floating plants, and peaceful tank mates. Avoid keeping with fin-nippers.

Diamond Tetra

Moenkhausia pittieri

Characins

6 cm Peaceful

A stunning, deep-bodied tetra endemic to Lake Valencia in Venezuela. Named for the brilliant, iridescent scales on its flanks that sparkle like diamonds under the right lighting. They are highly active, peaceful schooling fish that thrive in well-planted aquariums. Males develop spectacular, flowing fins as they mature.

Dwarf Pencilfish

Nannostomus marginatus

Characins

3.5 cm Peaceful

A tiny, peaceful schooling fish native to the Amazon and Orinoco basins. Known for their torpedo shape, striking horizontal stripes, and fascinating hovering behavior. Their tiny mouths make them one of the few truly dwarf-shrimp-safe fish. They require densely planted tanks with subdued lighting, soft acidic water, and gentle flow to thrive.

Ember Tetra

Hyphessobrycon amandae

Characins

2 cm Peaceful

The Ember Tetra is a striking, fiery orange-red nano fish native to the Araguaia River basin in Brazil. Extremely peaceful and active, they are perfect for planted and blackwater aquariums. They are tight schoolers and must be kept in groups to feel secure and display their best colors.

Emperor Tetra

Nematobrycon palmeri

Characins

5 cm Peaceful

A striking, robust schooling fish from Colombia. Unlike many tetras, they do not swim in a tight shoal, preferring to loosely associate while males stake out small territories to display to females. They feature a bold black lateral line and iridescent purple/blue hues.

False Rummy-Nose Tetra

Petitella georgiae

Characins

5 cm Peaceful

A small, peaceful, and highly active schooling fish known for its bright red snout and black-and-white striped tail. Often confused with the True Rummy-Nose (Hemigrammus rhodostomus) or Firehead Tetra (Hemigrammus bleheri), the 'False' Rummy-Nose is distinguished by red coloration that typically does not extend past the gills. They are excellent indicator fish; their red noses will pale if water quality drops. They require ample horizontal swimming space and pristine water conditions.