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Angelfish

Pterophyllum scalare

The 'Gliding Arrow' of the Amazon (15 cm long, 20 cm tall / 6x8 inches). A universally beloved freshwater icon, renowned for its jaw-dropping diamond-shaped body and unbelievably tall, majestic sail-like fins that allow it to hover completely motionless in the water. Despite its angelic name and elegant grace, it is a highly capable, calculated ambush predator that will happily inhale your expensive school of Neon Tetras under the cover of night.

Taxonomy

Class:Actinopteri

Order:Perciformes

Family:Cichlidae

Subfamily:Cichlasomatinae

Genus:Pterophyllum

Species:Pterophyllum scalare

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Water Temperature

24 - 28 °C

pH Value

6 - 7.5

Water type

Freshwater

Tank level

Middle

Adult size

15 cm

Minimum tank volume

>= 100 L

Minimum group

>= 2

2 - 15 dGH

1 - 8 dKH

TDS

40 - 305 ppm

Conductivity

63 - 477 uS/cm

Species description

Geographical Origin and Habitat: Vastly native to the massive, slow-moving rivers, swamps, and flooded floodplain forests of the massive Amazon and Orinoco Basins in South America. The Angelfish is a perfect evolutionary machine of 'Cryptic Camouflage': its flat, tall shape was explicitly designed by nature to allow it to hover completely motionless, perfectly disguised as a long, vertical hanging vine, root, or thick blade of swamp grass in the murky flooded forest, waiting to ambush prey.

Taxonomy and Morphology: A massive 'Diamond' or 'Rhombus' shaped cichlid that defies standard fish geometry. It is incredibly laterally compressed (as thin as a pancake or knife blade when looked at directly head-on). The mind-blowing aspect is its height: while an adult reaches about 15 cm (6 inches) from mouth to tail, it can easily exceed a staggering 20 cm (8+ inches) from the highest tip of its soaring dorsal fin to the bottom edge of its trailing anal fin. Furthermore, its pelvic fins have mutated into two incredibly long, stiff, mobile 'antennae' or 'feelers' (filaments) that trail far beneath it, used to sense its environment and communicate.

Social Behavior: The ambiguous royalty of the tank. As small silver juveniles, they are highly gregarious, happily schooling tightly together in a beautiful cloud in the middle of the aquarium. But when they reach sexual maturity (about a year old), civil war breaks out: they fracture into fiercely protective, territorial, and monogamous pairs that will aggressively claim entire corners of the tank. They are 'Static Ambush Predators': they spend hours floating perfectly still mid-water, angled slightly downward with intense focus, before exploding forward in a massive burst of speed, violently snapping their vacuum-like mouth shut to engulf smaller fish.

Coloration and Sexual Dimorphism: Intensively commercially bred into dozens of jaw-dropping 'Morphs'. Sizing up a male and female is nearly impossible unless they are actively laying eggs. The stunning, classic 'Wild Type' (Silver) features a brilliant, mirror-like silver body crossed by three or four thick, striking, ink-black vertical stripes (perfect reed-grass camouflage), often with glowing red-amber eyes and a slightly metallic blue back. Modern masterpieces include the 'Black Lace' (solid jet-velvet black), the 'Marble' (a chaotic, stunning mosaic of gold, black, and white splotches), and the highly-prized 'Koi' Angelfish (creamy white base heavily splattered with massive, glowing bright orange/yellow and red patches on its head and back).

Care, breeding and tankmates

Aquarium Setup: HEIGHT IS MANDATORY for proper growth. You need a tank minimum of 100 cm long (40 inches), BUT CRITICALLY, AT LEAST 50-60 CM TALL (20-24 inches tall / 40-55+ gallons). If kept in short tanks, their majestic, towering fins will become permanently stunted, bent, and atrociously deformed. THE VERTICAL FOREST: To provide massive comfort and curb aggression, heavily plant the back and sides of the tank with towering, thick vertical plants (like Amazon Swords or Giant Vallisneria jungle) and massive pieces of vertical driftwood/branch wood. They love to wedge themselves sideways between these tall vertical structures and levitate safely. They despise and will fight heavy, turbulent water currents (like powerheads), preferring slow, calm flow.

Diet and Feeding: Highly capable Micro-Predator (Omnivorous). Their mouth opens shockingly wide like an umbrella. Feed them a core diet of ultra-premium, slow-sinking cichlid granules or high-grade flakes. However, they are highly carnivorous and will go absolutely insane for frozen or freeze-dried Bloodworms (their favorite meal in the universe), brine shrimp, and Daphnia. DO NOT overfeed: Angelfish are legendary for lacking a 'fullness' sensor; they will frantically beg and gorge on food until they become violently bloated, constipated, and drop dead.

Water Quality: Typical Amazonian/Riverine water. Thankfully, decades of captive breeding have made them incredibly adaptable to standard municipal tap water. Tolerates pH heavily from slightly acidic to neutral/basic (6.0 - 7.4). Low to medium GH (3-10). Warm temperature is highly recommended: 24-28°C (75-82°F) (raising it to 82°F will often trigger instant spawning in pairs). Pristine water is needed to keep their incredibly long, fragile fin-tips from rotting away.

Compatibility and Cohabitation: THE GREAT NEON TETRA TRAGEDY: The biggest mistake made globally in the hobby. Beginners buy tiny Angelfish and put them in a tank with expensive schools of tiny Neon Tetras. For a year, it's peace. Then the Angelfish matures, and one night it switches into ambush mode, hovering in the dark behind a plant. In a single, lightning-fast strike, it inhales your expensive Neon whole. The next morning, your school is gone. ANGELS DEMAND LARGE, SLOW FRIENDS: Keep them with medium-to-large, robust Tetras (like Rummy-Nose, Lemon Tetras, Bleeding Heart Tetras), peaceful bottom Corydoras, or Dwarf Cichlids (Rams/Apistos). ABSOLUTE BAN ON FIN-NIPPERS: Never, ever put them in a tank with hyperactive, nipping fish like Tiger Barbs or Serpae Tetras. These bullies will brutally attack, shred, and rip the majestic, slow-moving Angelfish's trailing fins into rotting, bloody tatters, terrifying the Angel to death.

Aquarium Breeding: Magnificent, fiercely defensive 'Substrate Spawners' on vertical surfaces. It's almost impossible to sex them, so buy a group of 6 juveniles and wait a year for a pair to violently separate themselves from the group. The bonded pair will aggressively clear off a massive, broad vertical leaf (like an Amazon Sword plant) or the glass/filter tube in the corner. The female lays rows of up to 400 sticky eggs while the male follows, fertilizing them. They are terrifyingly protective parents: they will ferociously attack and batter fish twice their size to defend the eggs. Both parents take turns meticulously fanning the massive carpet of eggs until a massive cloud of tiny, wriggling 'fry' detaches and swims.

Risks and Diseases: 1. THE MIDNIGHT ASSASSIN (Dietary Predation): The absolutely guaranteed, silent, overnight massacre of any 'Nano/Neon' fish swimming anywhere in the tank that can physically fit inside the adult Angelfish's vacuum mouth. 2. Horrendous, lethal bacterial 'Fin Rot' destroying the fish's towering, magnificent dorsal sails, caused by housing them with aggressive, fast-moving 'Fin-Nipping' barbs or tetras. 3. Irreversible stunting, bent fins, and skeletal malformations if the juvenile is cruelly forced to grow in a shallow, suffocating tank with low ceilings.

Geographic Origin and Distribution

Vastly native to the massive, slow-moving rivers, swamps, and flooded floodplain forests of the massive Amazon and Orinoco Basins in South America. The Angelfish is a perfect evolutionary machine of 'Cryptic Camouflage': its flat, tall shape was explicitly designed by nature to allow it to hover completely motionless, perfectly disguised as a long, vertical hanging vine, root, or thick blade of swamp grass in the murky flooded forest, waiting to ambush prey.

Origin

Amazon, Orinoco, and Guianas

Fish profile

Temperament: Semi-aggressive
Diet: Omnivore
Life expectancy: 10+ years
Sex ratio: Pair
Feeding frequency: Twice daily
Bioload: High
Flow: Strong
Jump risk: No
Reproduction: Oviparous
Compatibility & tankmates: They are peaceful towards suitably sized tankmates. They will actively predate on very small fish. Avoid housing them with aggressive cichlid species.
Tank level: Middle

FishBase

Window to the official scientific data of the species

Data synced on: 06/15/2026

Scientific Parameters & Models

Trophic level: 3.6 ± 0.59 se
Resilience: High (less than 15 months)
Phylogenetic uniqueness (PD50): 0.625
Bayesian Length-Weight: a = 0.03236, b = 2.98

Image gallery

Licensed images linked to the species or, when marked, to the closest representative taxon.

Related species

Recommendations grouped by close relatives, companion choices, and similar care.

Variants and close relatives

Same atlas type, nearby scientific identity, genus, or family.

Kraussii Basketmouth (Caquetaia kraussii)

Caquetaia kraussii

Species description

Care, breeding and tankmates

Geographic Origin and Distribution

Origin

Fish profile

Scientific Parameters & Models

Image gallery

Related species

Variants and close relatives

Kraussii Basketmouth (Caquetaia kraussii)

Diadem Cichlid (Aequidens diadema)

Oscar

Redbreast Acara

Peacock Bass (Butterfly Cichla)

Amazon Cichlasoma (Cichlasoma amazonarum)

Keyhole cichlid

Paraguay Mouthbrooder (Bujurquina vittata)

African Butterfly Cichlid

Red-eye Krobia

Cockatoo Cichlid

Black Acara (Two-spot Cichlid)

Double-spot Acara (Aequidens pallidus)

Regan's Dwarf Pike Cichlid

Red-tailed apisto

Three-Stripe Dwarf Cichlid (Apistogramma trifasciata)

Recommended companions

Ammannia sp. 'Bonsai'

Bacopa sp. "Japan"

Bolbitis heteroclita

Arrowhead Anubias

Bucephalandra motleyana "Braun-rot narrow"

Bucephalandra motleyana "Riam Macam"

Anubias

Anubias nana

Bucephalandra motleyana "Braun-rot" ("Serimbu")

Bucephalandra motleyana "Kapit"

Bucephalandra motleyana "Pancuraji"

Bucephalandra sp. "Bukit Kelam / Sintang"

Bucephalandra sp. "Melawi"

Bucephalandra pygmaea "Bukit Kelam / Sintang"

Bucephalandra pygmaea "Kapit"

Bucephalandra sordidula

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Black Phantom Tetra

Balbus Tetra

Threadfin Acara

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Blackmask Corydoras

Dawn Tetra

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Big-Eyed Ancistrus (L144a)