Freshwater Species Library

Aquarium Care Guides

Find practical freshwater fish profiles covering tank size, water parameters, temperament, diet, group size, and compatible tank mates.

Fish Care Guide Rolodex

Showing 100 of 100 guides

Amano Shrimp

Caridina multidentata

Excellent algae-eating shrimp for peaceful planted aquariums, with larvae that require saltwater conditions to develop.

Care: Easy
Tank: 10+ gal
Nature: Peaceful

American Flagfish

Jordanella floridae

Colorful North American killifish often used for algae control, but territorial males and plant grazing require planning.

Care: Intermediate
Tank: 20+ gal
Nature: Semi-Aggressive

Angelfish

Pterophyllum scalare

Tall-bodied freshwater cichlid popular in larger planted aquariums.

Care: Intermediate
Tank: 29+ gal
Nature: Semi-Aggressive

Betta

Betta splendens

Popular freshwater fish known for vibrant colors and territorial behavior.

Care: Easy
Tank: 5+ gal
Nature: Semi-Aggressive

Black Ghost Knifefish

Apteronotus albifrons

Large nocturnal weakly electric fish requiring dim cover, a tight lid, peaceful tankmates too large to swallow, and careful medication choices.

Care: Advanced
Tank: 90+ gal
Nature: Semi-Aggressive

Black Moor Goldfish

Carassius auratus

Slow fancy goldfish with telescope eyes, best kept away from sharp decor and fast-feeding tankmates.

Care: Intermediate
Tank: 30+ gal
Nature: Peaceful

Black Neon Tetra

Hyphessobrycon herbertaxelrodi

Hardy peaceful tetra with a bright pale stripe over a black body, best displayed in groups over dark substrate and plants.

Care: Easy
Tank: 15+ gal
Nature: Peaceful

Bloodfin Tetra

Aphyocharax anisitsi

Hardy active tetra marked by red fins, useful for peaceful community tanks with swimming space.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Boesemani Rainbowfish

Melanotaenia boesemani

Large active rainbowfish prized for bold color, best kept in groups with open swimming space and robust community tankmates.

Care: Intermediate
Tank: 55+ gal
Nature: Peaceful

Bolivian Ram

Mikrogeophagus altispinosus

Hardier dwarf cichlid than the German Blue Ram, usually suitable for calm community tanks with soft substrate and hiding places.

Care: Intermediate
Tank: 20+ gal
Nature: Peaceful

Brilliant Rummynose Tetra

Petitella bleheri

Tight-schooling soft-water tetra often used as a visible indicator of stable community tank conditions.

Care: Intermediate
Tank: 20+ gal
Nature: Peaceful

Bristlenose Pleco

Ancistrus cirrhosus

Manageable algae-grazing pleco that stays smaller than common plecos but still adds meaningful waste load.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Bubble Eye Goldfish

Carassius auratus

Delicate fancy goldfish with fluid-filled eye sacs, best kept in species-style aquariums without sharp decor, strong flow, or fast tankmates.

Care: Advanced
Tank: 30+ gal
Nature: Peaceful

Buenos Aires Tetra

Hyphessobrycon anisitsi

Lively larger tetra that is hardy and active, but likely to graze soft aquarium plants.

Care: Easy
Tank: 30+ gal
Nature: Semi-Aggressive

Butterfly Splitfin

Ameca splendens

Robust goodeid livebearer from Mexican highland waters, best maintained in groups with room and durable companions.

Care: Advanced
Tank: 30+ gal
Nature: Semi-Aggressive

Cardinal Tetra

Paracheirodon axelrodi

Brightly colored soft-water tetra best kept in a larger group in calm, established community aquariums.

Care: Intermediate
Tank: 20+ gal
Nature: Peaceful

Celebes Rainbowfish

Marosatherina ladigesi

Slender Sulawesi rainbowfish for clean well-oxygenated aquariums, best kept in large groups.

Care: Intermediate
Tank: 20+ gal
Nature: Peaceful

Celestial Pearl Danio

Danio margaritatus

Tiny spotted danio for planted nano aquariums, best kept with gentle tankmates and plenty of cover.

Care: Intermediate
Tank: 10+ gal
Nature: Peaceful

Cherry Barb

Puntius titteya

Peaceful small barb whose males color intensely red, best kept in planted groups with gentle community fish.

Care: Easy
Tank: 15+ gal
Nature: Peaceful

Cherry Shrimp

Neocaridina davidi

Hardy dwarf shrimp that grazes biofilm and algae, best kept in colonies in mature planted tanks without predatory fish.

Care: Easy
Tank: 5+ gal
Nature: Peaceful

Chili Rasbora

Boraras brigittae

Very small blackwater schooling rasbora best suited to mature planted nano tanks with tiny peaceful tankmates.

Care: Intermediate
Tank: 5+ gal
Nature: Peaceful

Clown Killifish

Epiplatys annulatus

Tiny striped surface killifish with a colorful tail, best in covered planted nano tanks with calm water.

Care: Intermediate
Tank: 5+ gal
Nature: Peaceful

Clown Loach

Chromobotia macracanthus

Large long-lived social loach with bold color, often sold small but needing a group and a very large mature aquarium.

Care: Advanced
Tank: 100+ gal
Nature: Peaceful

Cockatoo Cichlid

Apistogramma cacatuoides

Popular Apistogramma dwarf cichlid with strong cave-territory behavior, best kept with structure, leaf litter, and calm tankmates.

Care: Intermediate
Tank: 20+ gal
Nature: Semi-Aggressive

Common Goldfish

Carassius auratus

Hardy long-bodied goldfish with heavy waste output and large adult size, better suited to large aquariums or ponds than bowls.

Care: Easy
Tank: 75+ gal
Nature: Peaceful

Congo Tetra

Phenacogrammus interruptus

Larger African schooling tetra with iridescent color and flowing fins, needing open swimming room and peaceful companions.

Care: Intermediate
Tank: 40+ gal
Nature: Peaceful

Convict Cichlid

Amatitlania nigrofasciata

Tough Central American cichlid famous for pair bonding and prolific breeding, but too territorial for ordinary community aquariums.

Care: Intermediate
Tank: 30+ gal
Nature: Aggressive

Corydoras Catfish

Corydoras paleatus

Bottom-dwelling schooling catfish commonly kept in freshwater tanks.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Crystal Red Shrimp

Caridina cantonensis

Selectively bred bee shrimp variety that rewards stable soft-water setups but is less forgiving than Neocaridina shrimp.

Care: Advanced
Tank: 5+ gal
Nature: Peaceful

Discus

Symphysodon discus

Iconic warm-water cichlid that needs stable soft acidic conditions, clean water, and calm tankmates suited to high temperatures.

Care: Advanced
Tank: 75+ gal
Nature: Peaceful

Dwarf Chain Loach

Ambastaia sidthimunki

Small social loach with chain-like markings, best kept in groups with structure and soft substrate.

Care: Intermediate
Tank: 30+ gal
Nature: Peaceful

Dwarf Gourami

Trichogaster lalius

Small colorful labyrinth fish that works as a calm focal species in planted tanks with gentle tankmates.

Care: Intermediate
Tank: 10+ gal
Nature: Peaceful

Dwarf Neon Rainbowfish

Melanotaenia praecox

Active smaller rainbowfish with bright iridescent color, best kept in groups with room to swim.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Dwarf Pencilfish

Nannostomus marginatus

Tiny surface-to-midwater characin for quiet planted or blackwater nano tanks with very peaceful companions.

Care: Intermediate
Tank: 10+ gal
Nature: Peaceful

Electric Yellow Cichlid

Labidochromis caeruleus

Popular Lake Malawi mbuna that is relatively mild for the group, but still belongs in hard alkaline rockwork aquariums with compatible cichlids.

Care: Intermediate
Tank: 55+ gal
Nature: Semi-Aggressive

Ember Tetra

Hyphessobrycon amandae

Tiny orange schooling tetra suited to peaceful planted nano and small community aquariums.

Care: Easy
Tank: 10+ gal
Nature: Peaceful

Endler's Livebearer

Poecilia wingei

Tiny active livebearer with vivid male coloration, best kept in groups in planted tanks with stable mineral-rich water.

Care: Easy
Tank: 10+ gal
Nature: Peaceful

Firemouth Cichlid

Thorichthys meeki

Medium Central American cichlid with dramatic red throat displays, manageable with space and robust tankmates.

Care: Intermediate
Tank: 40+ gal
Nature: Semi-Aggressive

Freshwater Butterflyfish

Pantodon buchholzi

Specialized African surface predator with jumping ability, needing a tight lid, floating cover, low current, and surface-oriented foods.

Care: Advanced
Tank: 30+ gal
Nature: Semi-Aggressive

German Blue Ram

Mikrogeophagus ramirezi

Colorful dwarf cichlid for warm soft-water aquariums, peaceful outside breeding but sensitive to water quality and unstable conditions.

Care: Advanced
Tank: 20+ gal
Nature: Peaceful

Glass Catfish

Kryptopterus vitreolus

Transparent schooling catfish that needs groups, calm tankmates, and stable clean water to avoid stress.

Care: Intermediate
Tank: 30+ gal
Nature: Peaceful

Glowlight Tetra

Hemigrammus erythrozonus

Peaceful shoaling tetra with a bright lateral stripe, best displayed in dim planted community tanks.

Care: Easy
Tank: 15+ gal
Nature: Peaceful

Golden Wonder Killifish

Aplocheilus lineatus

Hardy surface predator that needs a tight lid and tankmates too large to swallow.

Care: Intermediate
Tank: 20+ gal
Nature: Semi-Aggressive

Green Severum

Heros severus

Large relatively mild South American cichlid that still needs space, filtration, and durable aquascaping.

Care: Intermediate
Tank: 75+ gal
Nature: Semi-Aggressive

Guppy

Poecilia reticulata

Colorful livebearing fish ideal for beginner community tanks.

Care: Easy
Tank: 10+ gal
Nature: Peaceful

Harlequin Rasbora

Trigonostigma heteromorpha

Hardy peaceful rasbora that shows best in groups with subdued light, plants, and open swimming space.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Honey Gourami

Trichogaster chuna

Small peaceful gourami suited to calm freshwater community tanks.

Care: Easy
Tank: 10+ gal
Nature: Peaceful

Jack Dempsey Cichlid

Rocio octofasciata

Bold Central American cichlid with strong territorial behavior, best kept with space and similarly robust tankmates.

Care: Intermediate
Tank: 75+ gal
Nature: Aggressive

Keyhole Cichlid

Cleithracara maronii

Shy peaceful South American cichlid for planted community aquariums, needing cover and avoiding aggressive or boisterous tankmates.

Care: Easy
Tank: 30+ gal
Nature: Peaceful

Kissing Gourami

Helostoma temminckii

Large gourami known for mouth-locking displays, needing space and sturdy tankmates as it matures.

Care: Intermediate
Tank: 55+ gal
Nature: Semi-Aggressive

Kribensis

Pelvicachromis pulcher

Hardy West African dwarf cichlid with strong cave-spawning behavior, generally manageable but territorial when breeding.

Care: Easy
Tank: 20+ gal
Nature: Semi-Aggressive

Kuhli Loach

Pangio kuhlii

Nocturnal eel-shaped loach that needs soft hiding places, a secure lid, and the company of its own kind.

Care: Intermediate
Tank: 20+ gal
Nature: Peaceful

Lake Kutubu Rainbowfish

Melanotaenia lacustris

Larger blue rainbowfish that needs a group, open swimming space, and clean moderately hard water.

Care: Intermediate
Tank: 55+ gal
Nature: Peaceful

Least Killifish

Heterandria formosa

Very small livebearer for mature planted nano aquariums, best kept in groups with gentle tankmates or as a species-focused colony.

Care: Intermediate
Tank: 5+ gal
Nature: Peaceful

Lemon Tetra

Hyphessobrycon pulchripinnis

Long-established community tetra that develops yellow highlights and confident behavior when kept in a proper school.

Care: Easy
Tank: 15+ gal
Nature: Peaceful

Malaysian Trumpet Snail

Melanoides tuberculata

Burrowing livebearing snail that stirs substrate and consumes leftover food, but can multiply quickly when aquariums are overfed.

Care: Easy
Tank: 5+ gal
Nature: Peaceful

Molly

Poecilia sphenops

Adaptable livebearer that does best in clean stable aquariums with harder alkaline water and regular vegetable matter in the diet.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Moonlight Gourami

Trichopodus microlepis

Graceful pale gourami for calm planted aquariums with warm water and gentle companions.

Care: Easy
Tank: 30+ gal
Nature: Peaceful

Mystery Snail

Pomacea bridgesii

Large peaceful apple snail kept for cleanup and personality, requiring calcium-rich water and access to the surface for breathing.

Care: Easy
Tank: 5+ gal
Nature: Peaceful

Neon Tetra

Paracheirodon innesi

Small peaceful schooling fish commonly kept in planted freshwater community aquariums.

Care: Easy
Tank: 10+ gal
Nature: Peaceful

Odessa Barb

Pethia padamya

Colorful peaceful barb with a red lateral stripe in mature males, best kept in groups in active community tanks.

Care: Easy
Tank: 30+ gal
Nature: Peaceful

Oranda Goldfish

Carassius auratus

Fancy goldfish recognized by its headgrowth, requiring gentle flow, clean water, and similarly slow tankmates.

Care: Intermediate
Tank: 30+ gal
Nature: Peaceful

Oscar

Astronotus ocellatus

Large intelligent predatory cichlid with heavy waste output, requiring a spacious aquarium, strong filtration, and carefully chosen tankmates.

Care: Intermediate
Tank: 75+ gal
Nature: Aggressive

Otocinclus Catfish

Otocinclus vittatus

Small peaceful algae grazer best added to mature planted tanks with stable water and supplemental vegetable foods.

Care: Intermediate
Tank: 10+ gal
Nature: Peaceful

Panda Cory

Corydoras panda

Small peaceful Corydoras that works well in groups on soft substrate with calm community tankmates.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Paradise Fish

Macropodus opercularis

Hardy cool-tolerant labyrinth fish with strong territorial behavior, best planned around as the dominant focal species.

Care: Intermediate
Tank: 20+ gal
Nature: Semi-Aggressive

Pea Puffer

Carinotetraodon travancoricus

Tiny but territorial freshwater puffer best treated as a specialist species, requiring dense cover and meaty foods such as snails and frozen prey.

Care: Advanced
Tank: 10+ gal
Nature: Semi-Aggressive

Peacock Gudgeon

Tateurndina ocellicauda

Colorful small gudgeon that makes a distinctive focal fish in planted aquariums with caves and peaceful tankmates.

Care: Intermediate
Tank: 15+ gal
Nature: Peaceful

Pearl Gourami

Trichopodus leerii

Graceful peaceful gourami suited to planted community aquariums where it can act as a larger focal fish.

Care: Easy
Tank: 30+ gal
Nature: Peaceful

Peter's Elephantnose Fish

Gnathonemus petersii

Sensitive weakly electric mormyrid that needs subdued lighting, soft sand, peaceful feeding conditions, and excellent water stability.

Care: Advanced
Tank: 55+ gal
Nature: Semi-Aggressive

Platy

Xiphophorus maculatus

Hardy peaceful livebearer available in many domestic color forms, well suited to community aquariums with moderately hard water.

Care: Easy
Tank: 10+ gal
Nature: Peaceful

Pygmy Cory

Gastrodermus pygmaeus

Tiny shoaling Corydoras relative that uses both lower and mid-water areas in peaceful planted nano tanks.

Care: Intermediate
Tank: 10+ gal
Nature: Peaceful

Rainbow Shark

Epalzeorhynchos frenatum

Territorial bottom-oriented cyprinid with red fins, best housed singly with robust tankmates and defined caves.

Care: Intermediate
Tank: 55+ gal
Nature: Semi-Aggressive

Ranchu Goldfish

Carassius auratus

High-grade dorsal-less fancy goldfish prized in Japanese keeping traditions, requiring gentle flow, excellent filtration, and smooth decor.

Care: Advanced
Tank: 30+ gal
Nature: Peaceful

Red Eye Tetra

Moenkhausia sanctaefilomenae

Robust schooling tetra with a red eye mark and silver body, suitable for active community aquariums.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Red Tail Shark

Epalzeorhynchos bicolor

Striking black cyprinid with a red tail, territorial as it matures and best kept as the only sharklike bottom fish.

Care: Intermediate
Tank: 55+ gal
Nature: Semi-Aggressive

Reticulated Hillstream Loach

Sewellia lineolata

Specialized stream loach for cool, oxygen-rich aquariums with strong flow, rockwork, and established biofilm.

Care: Advanced
Tank: 20+ gal
Nature: Peaceful

Rope Fish

Erpetoichthys calabaricus

Snake-like primitive fish that needs a tight lid, meaty foods, and tankmates too large to swallow.

Care: Advanced
Tank: 75+ gal
Nature: Semi-Aggressive

Rosy Barb

Pethia conchonius

Hardy active barb with rosy male coloration, adaptable but likely to graze soft plants.

Care: Easy
Tank: 30+ gal
Nature: Peaceful

Sailfin Molly

Poecilia latipinna

Larger molly with an impressive dorsal fin, requiring more swimming space and stable hard alkaline water than smaller livebearers.

Care: Intermediate
Tank: 30+ gal
Nature: Peaceful

Scissortail Rasbora

Rasbora trilineata

Peaceful active rasbora with a forked tail pattern, requiring groups and open swimming space.

Care: Easy
Tank: 30+ gal
Nature: Peaceful

Senegal Bichir

Polypterus senegalus

Hardy predatory bichir with primitive lungs and bottom-focused behavior, requiring secure lids and large tankmates.

Care: Advanced
Tank: 90+ gal
Nature: Semi-Aggressive

Serpae Tetra

Hyphessobrycon eques

Bright red tetra with occasional fin-nipping tendencies, best kept in larger groups with active tankmates.

Care: Easy
Tank: 20+ gal
Nature: Semi-Aggressive

Siamese Algae Eater

Crossocheilus oblongus

Active algae-grazing cyprinid valued in planted tanks, needing swimming room and accurate identification from similar trade species.

Care: Easy
Tank: 30+ gal
Nature: Peaceful

Silver Dollar

Metynnis argenteus

Fast schooling characin related to piranhas but mostly herbivorous, needing open swimming space and durable or artificial planting.

Care: Intermediate
Tank: 75+ gal
Nature: Peaceful

Sparkling Gourami

Trichopsis pumila

Tiny croaking labyrinth fish for quiet, heavily planted nano aquariums with very small peaceful tankmates.

Care: Intermediate
Tank: 10+ gal
Nature: Peaceful

Sterbai Cory

Hoplisoma sterbai

Warm-water Corydoras suited to peaceful community aquariums, especially tanks that run too warm for cooler cory species.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Swordtail

Xiphophorus hellerii

Active larger livebearer known for the male's tail extension, best kept in roomy covered aquariums with peaceful robust tankmates.

Care: Easy
Tank: 30+ gal
Nature: Peaceful

Threadfin Rainbowfish

Iriatherina werneri

Delicate small rainbowfish with long male fins, needing gentle tankmates and small foods.

Care: Intermediate
Tank: 20+ gal
Nature: Peaceful

Three Spot Gourami

Trichopodus trichopterus

Hardy larger gourami available in several color forms, requiring space and careful tankmate selection due to territorial males.

Care: Easy
Tank: 30+ gal
Nature: Semi-Aggressive

Tiger Barb

Puntigrus tetrazona

Active striped barb that can nip fins when under-grouped, best kept in a large school with sturdy tankmates.

Care: Easy
Tank: 30+ gal
Nature: Semi-Aggressive

Upside-Down Catfish

Synodontis nigriventris

Small Synodontis catfish known for inverted swimming, best kept with cover, driftwood, and peaceful medium-sized tankmates.

Care: Intermediate
Tank: 30+ gal
Nature: Peaceful

Weather Loach

Misgurnus anguillicaudatus

Cool-water burrowing loach that grows large and needs smooth substrate, secure lids, and regionally legal sourcing.

Care: Intermediate
Tank: 55+ gal
Nature: Peaceful

White Cloud Mountain Minnow

Tanichthys albonubes

Cool-water schooling minnow valued for hardiness, peaceful behavior, and beginner-friendly care.

Care: Easy
Tank: 10+ gal
Nature: Peaceful

Wrestling Halfbeak

Dermogenys pusilla

Surface-oriented livebearer with a delicate elongated jaw, requiring a covered tank, calm surface space, and careful feeding.

Care: Advanced
Tank: 20+ gal
Nature: Semi-Aggressive

X-Ray Tetra

Pristella maxillaris

Adaptable transparent-bodied tetra that tolerates a wide range of community conditions when kept in a group.

Care: Easy
Tank: 15+ gal
Nature: Peaceful

Yoyo Loach

Botia almorhae

Active social loach for larger aquariums, useful with robust tankmates but too boisterous for tiny or timid fish.

Care: Intermediate
Tank: 40+ gal
Nature: Semi-Aggressive

Zebra Danio

Danio rerio

Active hardy schooling fish that does best with open swimming room and tankmates that tolerate its energy.

Care: Easy
Tank: 20+ gal
Nature: Peaceful

Zebra Loach

Botia striata

Social striped loach for active community tanks, requiring groups, clean water, and smooth substrate.

Care: Easy
Tank: 30+ gal
Nature: Peaceful

Zebra Nerite Snail

Vittina natalensis

Small algae-grazing snail that is plant safe and will not reproduce successfully in freshwater, but needs mineral-rich water for shell health.

Care: Easy
Tank: 5+ gal
Nature: Peaceful