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.
Apistogramma baenschi
A striking South American dwarf cichlid native to Peru. Males boast a dramatically high, sail-like dorsal fin and vibrant blue/yellow coloration. They are cave spawners that require soft, acidic water and a sand substrate for their natural earth-sifting behaviors.
Apistogramma borellii
A hardy and relatively peaceful dwarf cichlid native to the Paraguay River basin. Uniquely among Apistogramma, they tolerate cooler (sub-tropical) water temperatures. They are excellent for planted community tanks but require sandy substrates to sift and leaf litter or caves to establish territories.
Apistogramma elizabethae
A rare and highly sought-after dwarf cichlid native to the extremely acidic blackwaters of the Rio Uaupés basin in Brazil. Known for its spectacular finnage and sensitivity to water parameters. They require pristine, very soft, and acidic water, alongside a fine sand substrate for sifting.
Apistogramma macmasteri
A stunning, brightly colored dwarf cichlid native to the Meta River basin in Colombia. They are intelligent, sand-sifting micropredators that form complex social hierarchies. While relatively peaceful in a community setting, they become fiercely territorial during breeding. Soft, sandy substrate is strictly required for their gill-sifting feeding behavior.
Apistogramma panduro
A stunning and personality-filled dwarf cichlid from the blackwaters of Peru. Unlike many other Apistogramma species that form harems, A. panduro forms strong, monogamous pair bonds. They are heavily sexually dimorphic and require soft, acidic water, sandy substrate for sifting, and plenty of visual barriers like driftwood and leaf litter.
Apistogramma uaupesi
A stunning and rare dwarf cichlid native to the blackwater Rio Uaupés basin in South America. They are strictly blackwater fish, requiring very soft, acidic water and dim lighting to thrive. Males are famous for their spectacular, sail-like dorsal fins and lyretails. Like most Apistogramma, they are harem breeders and require complex environments with sightline breaks.
Apistogramma viejita
A striking South American dwarf cichlid native to the Orinoco River basin. True A. viejita are extremely rare in the hobby; most sold under this name are A. macmasteri or hybrids. They are substrate-sifters that absolutely require sand to prevent gill damage. While generally peaceful in a community setting, they become fiercely territorial during breeding.
Pomacea maculata
One of the largest freshwater snails in the world, capable of reaching the size of a baseball or larger. Unlike the popular 'Mystery Snail' (Pomacea bridgesii) which is generally plant-safe, Pomacea maculata is a voracious herbivore that will systematically devour almost any live aquarium plant. They require heavy filtration due to their massive waste output and hard, calcium-rich water to prevent shell deterioration.
Arapaima gigas
One of the largest true freshwater fish in the world, native to the Amazon basin. Arapaima are obligate air-breathers and extreme predators. Due to their massive adult size and explosive growth rate, they are almost entirely unsuited for home aquaria and require highly specialized, heated, pond-sized enclosures.
Melanotaenia arfakensis
A lively and relatively rare schooling fish endemic to the fast-flowing streams of the Bird's Head Peninsula in West Papua. Known for their energetic swimming and beautiful subtle coloration, with dominant males displaying bright orange-red fins edged in black. As active swimmers, they require long aquariums with high oxygenation and moderate to high water flow.
Pao suvattii
A highly predatory freshwater pufferfish native to the Mekong basin. Named for its V-shaped, flattened head, it is a specialized ambush predator that buries itself in sand with only its eyes and upwards-facing mouth exposed. It is notoriously aggressive and will consume or fatally bite any tankmate, regardless of size. Must be kept strictly solitary.
Dawkinsia arulius
A robust, highly active schooling fish native to the fast-flowing rivers of southern India. Known for their striking vertical bars and the beautiful dorsal fin extensions developed by mature males. Because of their energetic swimming habits and size, they require highly oxygenated water, decent current, and a spacious aquarium with plenty of horizontal swimming room.
Corydoras tukano
A striking and relatively uncommon small Corydoras originating from the blackwater Rio Tiquié in the upper Rio Negro basin. Known for its prominent vertical black bands across a pale tan or golden body. Like all Corydoras, they are completely peaceful, highly social bottom dwellers that must be kept in groups. A fine sand substrate is absolutely critical to prevent damage to their delicate barbels as they constantly sift for food.
Scleropages formosus
A highly prized, CITES-protected 'monster fish' known as the Dragon Fish. They are powerful, surface-dwelling predators that require massive aquariums and pristine water quality. Notorious jumpers, they require heavy, secure lids. Because of intense territoriality, they must be kept strictly solitary or in large 'comm' (community) groups of 5+ to disperse aggression.
Mystus leucophasis
A fascinating but highly aggressive bagrid catfish from Myanmar that spends almost its entire life swimming inverted. Unlike the peaceful African Synodontis upside-down catfish, the Asian variety grows large, is fiercely territorial, and will predate on smaller tank mates. They require ample driftwood or caves to rest underneath during the day.
Anentome helena
A highly effective and popular carnivorous freshwater snail used primarily for pest snail control. They actively hunt and consume smaller snails like bladder, ramshorn, and pond snails. Featuring a striking yellow and dark brown spiraled shell, they are a functional and attractive addition to aquariums. Unlike many aquatic snails, they are not hermaphroditic and reproduce quite slowly.
Melanochromis auratus
The Auratus Cichlid is a stunning but notoriously aggressive Mbuna from Lake Malawi. They exhibit extreme sexual dimorphism. They are strictly rock-dwellers that graze on algae (aufwuchs). Due to their hyper-aggressive nature, they must be kept in species-only or carefully managed, overstocked Mbuna setups with a strict harem ratio (1 male to several females) to disperse aggression.
Metriaclima sp. "Aurora Yellow"
A striking and highly active Mbuna from Lake Malawi, scientifically described as Metriaclima mossambicum. Like most Mbuna, they are fiercely territorial rock-dwellers that require hard, alkaline water. They are specialized algae grazers (Aufwuchs feeders) and need a heavily plant-based diet to prevent deadly digestive issues like 'Malawi Bloat'. They must be kept in a harem structure (one male to multiple females) to disperse their severe aggression.
Scleropages jardinii
A massive, highly aggressive predatory fish native to Australia and New Guinea. Known for its distinct metallic, pearl-like scales and upward-facing mouth designed for surface feeding. It is notoriously territorial and intolerant of tank mates, making it a popular 'wet pet' for solitary setups. It is an absolute tank buster requiring a massive aquarium with a heavy, tightly secured lid to prevent fatal jumping.
Retropinna semoni
A slender, silvery schooling fish native to Australia. They are pelagic and found in huge numbers in the wild across freshwater rivers, billabongs, and brackish estuaries. Known for their distinct cucumber-like odor when handled. In the aquarium, they are highly sensitive to handling and require mature, stable water with plenty of open swimming space. Best kept in single-species setups or with very peaceful, temperate tank mates.
Chilatherina axelrodi
A highly active, colorful schooling fish native to Papua New Guinea. Known for a bluish-grey upper body and yellowish-white lower body divided by a dark lateral stripe. Like most rainbowfish, they are incredibly fast, active swimmers that require pristine water, moderate flow, and significant horizontal swimming space.
Copadichromis azureus
A stunning open-water 'Utaka' cichlid from Lake Malawi. Males develop a spectacular metallic blue coloration, making them popular centerpieces in African Cichlid tanks. Compared to rock-dwelling Mbuna, they are relatively peaceful open-water swimmers but still require ample swimming space and hard, alkaline water.
Badis badis
Known as the Chameleon Fish due to its ability to rapidly change color based on mood, environment, and dominance. They are deliberate, slow-moving micro-predators that often refuse dry flakes or pellets, requiring a diet of live or frozen foods (bloodworms, daphnia). They are notorious for decimating dwarf shrimp and small snail populations.
Geophagus sp. Bahia Red
The Bahia Red is a beautiful, earth-eating cichlid belonging to the Geophagus brasiliensis complex. They are highly sought after for their vivid red/orange hues and pearlescent spangling. Like all 'eartheaters', they require a fine sand substrate to exhibit their natural sifting behaviors. While generally peaceful for a cichlid, they become aggressively territorial during breeding.
