Freshwater angelfish are cichlids with flat, round bodies and triangular anal and dorsal fins. All species are from the Orinoco, Amazon, and Essequibo Rivers in South America. In the wild, freshwater angelfish tend to have long striped markings on their bodies that provide camouflage among plants and roots. As a result of selective breeding by fishkeeping enthusiasts or aquarists, many strains of the fish have been developed, including some without the distinctive stripes. These fish are easy to breed, semi-aggressive, and prefer a warm aquarium with an acidic environment.
Popular with aquarists for their unique appearance, the three recognized freshwater angelfish species belong to the genus Pterophyllum. This name comes from the Greek words for winged (pteron) and leaf (phyllon). Of the recognized species, most freshwater angelfish available to aquarists are P. scalare. This species was first described in 1823 by M.H.C. Lichtenstein.
P. scalare can be found in the Peruvian, Brazilian, and Colombian Amazon River basins. It prefers dense vegetation in which to hide, clear or silty water, and can also live in swamps. Its natural coloring is light with dark longitudinal stripes on its body. These stripes help this freshwater angelfish hide among the vegetation in the river. The majority of P. scalare available in stores are captive-bred.
Hearty enough for beginners, these fish thrive in a warm aquarium of approximately 80 degrees Fahrenheit (27 degrees Celsius). The water should have a pH of between six and eight. A dechlorinating agent is recommended if the water is chlorinated, but aerating the water will achieve the same effect in about 24 hours. Flake food and dried blood worms are appropriate foods for angelfish.
Freshwater angelfish can grow rather large with a body that is taller than it is long. The body can grow to 6 inches (15 centimeters) with a height of 8 inches (20 cm). As a result, angelfish require a tall tank that is big enough to give them sufficient space while growing to full size. A 50-gallon aquarium that is at least 18 inches (47 cm) deep is a sufficient size for between 12 and 15 fish. As the angelfish approach breeding size, half should be removed from the tank, leaving between six and seven individuals.
Although angels are usually considered to be semi-aggressive, their fins are vulnerable to nipping. More aggressive fish like some smaller tetras or barbs may nip at the longer fins. Angelfish are usually compatible with plecos, platies, and gouramis but may stalk neon tetras and guppies. Angels are comfortable in groups of at least three and ideally six or alone in an aquarium. In nonbreeding pairs or trios, the most aggressive may turn on the others.
When angelfish reach breeding age between six and 12 months, they form monogamous pairs. The pair will usually spawn on a flat surface like a piece of slate, the glass of their aquarium, or a plant leaf. The female deposits her eggs and then the male fertilizes them. The eggs will hatch after a few days, although sometimes the pair will eat them. Breeders may prefer to keep pairs in a bare aquarium and remove the eggs immediately after spawning to encourage the pair to spawn again.
Long, flowing fins, the flat, triangular body, and dramatic coloring attract many aquarists to freshwater angelfish. Selective breeding in captivity has resulted in many varieties. Some, like koi, are stripeless with brightly colored bodies, while others, like the pearlscale, have iridescent scales. The variety that most closely resembles the wild freshwater angelfish is silver. Freshwater angelfish are relatively simple to care for and offer aquarists many colorful and unique varieties to choose from.