Pterophyllum scalare, the species most commonly referred to as angelfish or freshwater angelfish, is the most common species of Pterophyllum held in captivity. It is native to the Amazon Basin in Peru, Colombia, and Brazil, particularly the Ucayali, Solimões and Amazon rivers, as well as the rivers of Amapá in Brazil, the Oyapock River in French Guiana and the Essequibo River in Guyana. It is found in swamps or flooded grounds where vegetation is dense and the water is either clear or silty. Its native water conditions range from a pH of 6.0 to 8.0, a water hardness range of 5 - 13 dH, and water temperature ranging from 24 to 30 °C (75 to 86 °F). This is the species of angelfish most frequently found in the aquarium trade. A similar (cross-breeding possible) P.scalare exist in the Orinocco. They are of same size and shape, the only difference are its stripes. The Orinocco P.scalare has thinner, but dual stripes.
As aquarium fish inbreeding is a problem with this fish. All strange colours are due to heavy inbreed. In nature this cichlid is as strong as most other of its weight, but strong individuals are very rare to find in today's aquarium trade. Hence P.scalare shall not be kept together with other South American cichlids. If the water isn't "hard" (max. 10 dGH, pH-level matter less for breeding, but should always be between 6.0 and 7.5), this fish play very easily after a rising of temperature (typically from +26/27C to +29/30C), but eggs may rot and their fry are extremely sensitive for water changes of all kind during several weeks. If eggs are laid in a separate tank, many may survive if parts of the water is changed daily but very slow. Filling a 100 litre tank with 10 - 15 litres every day, but the new water must be added during an hour or longer. Check pH of tap water, around 8 is OK. Use a thin hose from a bucket placed above the tank. Remove parents and feed with frozen red bloodworms, that is scratched with a very sharp blade (the result must be a "micronized mess") - otherwise use special liquid found in the trade.