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.
Aphyocharax anisitsi
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.
Andinoacara pulcher
A stunning and relatively peaceful South American cichlid. While they possess classic cichlid traits—such as digging and territoriality during breeding—they are generally far more tolerant of tank mates than their larger cousins (like the Green Terror). They will, however, eagerly consume any fish small enough to fit in their mouths (like Neon Tetras).
Pseudomugil cyanodorsalis
A tiny, highly active euryhaline species native to the mangrove swamps and tidal estuaries of Northern Australia. While biologically capable of surviving in pure freshwater or full marine conditions, they require a brackish aquarium (SG 1.005-1.015) to thrive, breed, and resist disease long-term. They are peaceful shoaling fish but spectacular jumpers, so a tight-fitting lid is absolutely mandatory.
Yasuhikotakia modesta
A large, active, and highly social river loach recognized by its bluish-grey body and vividly colored fins (yellow, orange, or red). They are known for making audible 'clicking' noises. While fascinating, they are boisterous and can be aggressive or fin-nipping if not kept in a proper hierarchy; keeping them in groups of 5+ is mandatory to diffuse conspecific aggression and prevent them from terrorizing tank mates.
Cyrtocara moorii
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.
Inpaichthys kerri
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.
Neocaridina zhangjiajiensis
A hardy, peaceful dwarf shrimp species closely related to the popular Cherry Shrimp. They are excellent scavengers that constantly graze on biofilm and algae. Due to their tiny size, they are extremely vulnerable to predation and are best kept in dedicated invertebrate setups or with very small, peaceful nano fish (like rasboras).
Andinoacara coeruleopunctatus
The Blue Point Cichlid (formerly Aequidens coeruleopunctatus) is a medium-sized Central and South American cichlid closely related to the Green Terror, but notably less aggressive. They are benthopelagic omnivores with a natural tendency to sift and dig through sandy substrates. While relatively peaceful for a cichlid of its size, it remains highly territorial during breeding and dominant males are completely intolerant of rival males.
Melanotaenia caerulea
A small, highly active, and colorful schooling fish native to the Kikori River system in Papua New Guinea. They are peaceful but require ample swimming space and a school of their own kind to thrive. Like most rainbowfish, they appreciate well-oxygenated, flowing water and are excellent jumpers. Males develop a striking blue hue with reddish horizontal stripes.
Cribroheros robertsoni
A stunning Central American cichlid known for its iridescent turquoise speckling and unique earth-eating behavior. It constantly sifts substrate through its gills to forage, making soft sand absolutely mandatory to prevent gill damage. While mildly tempered compared to many Central American cichlids, it becomes highly territorial when breeding.
Knodus borki
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.
Oreochromis aureus
A robust, large-growing African cichlid famous for its hardiness, high growth rate, and commercial value. In the aquarium, they are highly active, extremely messy, and will systematically destroy any live plants or intricate hardscape by digging massive crater nests. They are highly adaptable to various water conditions, including brackish water.
Lepomis macrochirus
A highly active and intelligent North American native fish. Known for their deep, laterally compressed bodies and the distinctive dark spot at the base of the dorsal fin. They are predatory and territorial, often treated as 'coldwater cichlids' by hobbyists. Because they grow large and are highly active, they require significant swimming space and heavy filtration.
Melanotaenia boesemani
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.
Mikrogeophagus altispinosus
A hardy and relatively peaceful dwarf cichlid native to the Amazon river basin. Compared to the popular German Blue Ram, the Bolivian Ram is larger, much more forgiving of water parameters, and prefers slightly cooler temperatures. They are eartheaters (geophagine) that sift through the substrate for food, making soft sand an absolute requirement to prevent gill damage.
Neolamprologus brevis
A fascinating miniature African Cichlid endemic to Lake Tanganyika, famous for making its home inside empty snail shells. Uniquely among Tanganyikan shell dwellers, the male and female Brevis will often share the exact same shell. They require hard, alkaline water, a sandy substrate (for burying their shells), and plenty of appropriately sized shells (like escargot shells) to thrive.
Rasbora einthovenii
The Brilliant Rasbora is a peaceful, highly active schooling fish native to the forest streams and peat swamps of Southeast Asia. Known for its shimmering silver body and distinct dark lateral stripe, they thrive in gently flowing, heavily planted blackwater setups with subdued lighting. They are known jumpers, requiring a tight-fitting lid.
Hemigrammus bleheri
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.
Ancistrus cf. cirrhosus
A highly popular, hardy, and relatively small suckermouth catfish. Excellent algae eaters that stay much smaller than Common Plecos, making them suitable for standard aquariums. They require dietary wood (driftwood) to aid in digestion and plenty of hiding caves.
Corydoras aeneus
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.
Ameiurus nebulosus
A highly adaptable, large North American catfish known for its distinct barbels and mottled brown skin. While incredibly hardy and tolerant of a wide range of water parameters, they are massive, opportunistic nocturnal predators. They will consume any tank mate small enough to fit in their cavernous mouths and produce substantial waste.
Caridina babaulti var. Brown
The Brown Camo Shrimp (Caridina babaulti) is a fascinating dwarf shrimp known for its ability to rapidly change color to match its surroundings, much like a chameleon. They are excellent scavengers and algae grazers. Unlike some highly sensitive Caridina species (like Crystal Reds), Babaulti are relatively hardy and can adapt to a wider range of water parameters, making them a great choice for planted nano tanks.
Hoplosternum littorale
A heavily armored, highly adaptable catfish native to South America. It possesses the unique ability to breathe atmospheric air using a modified intestine, allowing it to survive in oxygen-depleted swamps. They are peaceful but boisterous bottom-dwellers with voracious appetites. They constantly forage, which can result in the uprooting of delicate plants.
Pao turgidus
A heavily built, strictly freshwater pufferfish native to the Mekong basin in Southeast Asia. Often sold as part of the 'Target Puffer' complex, the Brown Puffer is a notorious ambush predator. They spend much of their time lurking among plants or partially buried in the substrate waiting for prey. They are highly aggressive, strictly solitary, and possess a sharp beak capable of crushing snails and fatally injuring tank mates.
