Freshwater Fish Profiles

Explore our growing database of freshwater fish species. Each profile includes detailed care requirements, compatibility data, and environmental needs to help you build the perfect aquarium.

Showing 1 - 24 of 85 Fish Profiles

African Butterfly Cichlid

Anomalochromis thomasi

Other
7.5 cm Mostly Peaceful

A peaceful, colorful dwarf cichlid from West Africa. Unlike many cichlids, it is plant-safe and generally suitable for community tanks. It is famous in the hobby as an efficient biological control for pest snails.

African Jewel Cichlid

Hemichromis bimaculatus

Cichlids - African
14 cm Aggressive

A strikingly beautiful but notoriously aggressive West African riverine cichlid. Unlike the alkaline-loving Rift Lake cichlids (e.g., Mbuna), Jewel Cichlids prefer neutral, softer water parameters. They are renowned for their brilliant red breeding dress and iridescent blue spots, but also for their extreme territoriality, especially when forming pairs and spawning. They are avid diggers and will uproot most plants.

Amano Shrimp

Caridina multidentata

Invertebrates
5 cm Peaceful

A highly popular, industrious freshwater shrimp renowned for its unmatched algae-eating abilities. Popularized by aquascaper Takashi Amano, they are significantly larger and hardier than most dwarf shrimp (like Cherry Shrimp). They are notorious food-thieves during feeding time and excellent escape artists, requiring a tight-fitting lid. Their larvae require saltwater to develop, so they will not overpopulate in a freshwater aquarium.

Amazon Leaf Fish

Monocirrhus polyacanthus

Other
8 cm Peaceful

A master of camouflage that perfectly mimics a dead leaf drifting in the water. This species is an extreme ambush predator with a protruding jaw that can swallow prey up to 75% of its own size. It is a 'specialist' species because nearly all specimens require live food (small fish/shrimp) and refuse dry or frozen foods. Requires acidic, blackwater conditions and zero flow.

Amazon Puffer

Colomesus asellus

Puffers
8 cm Mostly Peaceful

One of the few truly freshwater, community-safe pufferfish. Native to the Amazon basin, these energetic swimmers are known for their bumblebee-like stripes and erratic swimming patterns. Unlike most puffers, they are social and prefer to be kept in groups. CRITICAL WARNING: This species has the fastest-growing teeth of any puffer. They REQUIRE a daily diet of hard-shelled foods (snails, clams, crustaceans) or they will require manual dentistry (trimming) to prevent starvation.

Bee Shrimp (Crystal Red / Black)

Caridina cantonensis

Invertebrates
3 cm Peaceful

A sensitive, highly prized dwarf shrimp species known for its vivid red/white or black/white banding. Unlike the hardy Cherry Shrimp (Neocaridina), Bee Shrimp require cool, soft, acidic water and typically require active buffering soil to thrive. They are peaceful grazers perfect for specific biotope setups.

Betta (Siamese Fighting Fish)

Betta splendens

Anabantoids
7 cm Semi-Aggressive

The Siamese Fighting Fish is an aquarium icon known for its labyrinth organ (allowing air breathing) and vivid colors. While hardy, they require heated, filtered water (24-30°C). Males are solitary and fiercely territorial. Females are generally less ornate but can be kept in 'sororities' with strict precautions (minimum 5 females in 75L+).

Black Ghost Knifefish

Apteronotus albifrons

Oddballs
40 cm Semi-Aggressive

A fascinating nocturnal predator native to the Amazon basin. It lacks a dorsal fin and moves via a continuous undulating ventral fin, allowing it to swim backwards as easily as forwards. It generates a weak electrical field to navigate and hunt in the dark. Scaleless and highly sensitive to medications, it requires smooth hiding places (like PVC pipes or smooth driftwood). Will consume any fish small enough to fit in its surprisingly large mouth.

Blue Dolphin (Hap)

Cyrtocara moorii

Cichlids - African
25 cm Semi-Aggressive

A striking blue Lake Malawi Haplochromine cichlid famous for the pronounced nuchal hump (head bump) that develops in mature adults, resembling a dolphin. They are benthopelagic micro-predators that naturally follow digging fish in the wild to catch stirred-up morsels. While relatively peaceful for an African Cichlid, they grow very large and require extensive swimming space and hard, alkaline water.

Boeseman's Rainbowfish

Melanotaenia boesemani

Rainbowfish
10 cm Peaceful

An incredibly popular and active schooling fish endemic to the Ajamaru Lakes in West Papua, Indonesia (currently listed as Endangered in the wild by the IUCN due to overfishing and habitat loss, though commercially captive-bred). Famous for the mature male's spectacular blue and orange split-coloration. They require long tanks for active swimming, excellent oxygenation, and warm, hard, alkaline water to thrive.

Bronze Corydoras

Corydoras aeneus

Catfish
7 cm Peaceful

A highly popular, peaceful schooling catfish known for its armor-like scales (scutes) and active bottom-feeding behavior. They are essential clean-up crew members but require a dedicated sinking diet (not just leftovers). Sand substrate is strictly required to prevent erosion and infection of their sensitive barbels. They are 'gut breathers' and will occasionally dart to the surface to gulp atmospheric air.

Bumblebee Goby (Brackish)

Brachygobius xanthozonus

Gobies & Gudgeons
4.5 cm Mostly Peaceful

A miniature, bottom-dwelling goby famous for its striking black and yellow stripes. While they are often sold as freshwater fish and can survive in it temporarily, they are highly susceptible to fungal infections in fresh water and truly require a brackish setup (SG 1.002-1.005) to thrive long-term. They are notoriously picky eaters, often ignoring flakes in favor of live or frozen foods (like bloodworms or brine shrimp).

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.

Cherry Barb

Puntius titteya

Cyprinids
5 cm Peaceful

A peaceful, schooling cyprinid endemic to the shaded streams of Sri Lanka. Unlike many of its barb cousins, the Cherry Barb is not a fin-nipper and makes an excellent community fish. They thrive in heavily planted aquariums with subdued lighting and leaf litter. Males display a striking cherry-red color, especially during spawning.

Cherry Shrimp

Neocaridina davidi

Invertebrates
3 cm Peaceful

One of the most popular and hardy freshwater invertebrates in the hobby. They come in a rainbow of selectively bred colors. They are excellent scavengers and algae eaters, perfect for nano planted tanks. They are completely peaceful and have a negligible bioload, though they are highly vulnerable to predation by almost any fish with a mouth large enough to eat them.

Clown Killifish

Epiplatys annulatus

Killifish
3.5 cm Peaceful

A striking nano killifish resembling a tiny rocket. Native to West African swamps, they have distinct black and yellow vertical bands. They are strictly surface dwellers (top-level) and are non-annual, meaning they live longer than annual killifish (2-3+ years). They are notorious jumpers and require a tight lid.

Clown Knifefish

Chitala ornata

Oddballs
90 cm Aggressive

A massive, nocturnal predator native to Southeast Asia, widely known for the distinct row of ocellated spots above its anal fin. While sold as small silvery cute juveniles, they grow incredibly fast into nearly 1-meter giants that require immense aquariums. They are obligate carnivores and will eat any fish small enough to fit in their large mouths. They are shy during the day and require large hiding tubes or caves.

Clown Loach

Chromobotia macracanthus

Loaches
30 cm Peaceful

A highly popular but large-growing shoaling fish famous for eating nuisance snails. Known for their striking orange and black bands, they are highly social and must be kept in groups. They have no standard scales, making them sensitive to medications and prone to Ich, requiring pristine, warm water. They are known for their quirky behavior of sleeping on their sides or backs.

Convict Cichlid

Amatitlania nigrofasciata

Cichlids - Central American
15 cm Aggressive

One of the most ubiquitous and hardy cichlids in the hobby. Named for their black-and-white prison stripe pattern, Convicts are infamous for their intense aggression, especially when breeding (which they do readily). They are intelligent, wet pets that rearrange their tank décor constantly. Best kept in species-only tanks or with other robust Central American cichlids.

Demasoni Cichlid (Mbuna)

Chindongo demasoni

Cichlids - African
8 cm Highly Aggressive

A stunning but notoriously aggressive dwarf Mbuna from Lake Malawi. Known for its intense dark blue and black vertical stripes. They are strict herbivores (Aufwuchs grazers) and prone to 'Malawi Bloat' if fed high-protein diets. Due to extreme aggression toward their own kind, they require specific stocking densities.

Denison Barb (Roseline Shark)

Sahyadria denisonii

Cyprinids
15 cm Mostly Peaceful

An endangered, stunningly colored cyprinid endemic to the fast-flowing streams of the Western Ghats in India. Characterized by a torpedo-shaped body with a striking red line and black stripe. They are highly active, fast swimmers that require highly oxygenated water, strong flow, and cooler tropical temperatures. They are strictly shoaling fish and can be skittish if kept in small numbers.

Discus

Symphysodon aequifasciatus

Cichlids - South American
18 cm Mostly Peaceful

Known as the 'King of the Aquarium', Discus are stunning, heavily laterally-compressed cichlids. They are famous for their demanding husbandry, requiring high temperatures (28-32°C / 82-90°F), pristine water quality, and specialized diets. They are schooling fish that establish a strict pecking order and must be kept in groups to prevent intense bullying of a single weaker fish.

Dwarf Chain Loach

Ambastaia sidthimunki

Loaches
6 cm Peaceful

An incredibly active, highly social, and peaceful nano loach. Known for its distinct chain-like pattern, this species is an excellent alternative to Clown Loaches for smaller aquariums. They are fantastic snail hunters. They must be kept in groups of at least 6 to feel secure and display their entertaining, hyperactive shoaling behavior.

Dwarf Gourami

Trichogaster lalius

Anabantoids
7.5 cm Semi-Aggressive

A peaceful to semi-aggressive labyrinth fish native to South Asia. Famous for their brilliant metallic blue and red stripes. While generally suitable for community tanks, males are territorial toward each other and similar-looking fish. They are sensitive to water quality and prone to Iridovirus if stressed. Requires access to the surface to breathe.