Page 144 - Encyclopedia of Aquarium and Pond Fish, 3rd Edition

142 FRESHWATER FISH DIRECTORY

Symphysodon aequifasciatus

Blue Discus White fins Red eye
color
ORIGINS South America, from Rio Putumayo in Peru
eastward through the Amazon basin in Brazil.
SIZE 8 in (20 cm).
DIET Discus foods and small live foods.
WATER Temperature 75–84°F (24–29°C); soft
(50–100 mg/l) and acidic (pH 6.0).
TEMPERAMENT Quite placid and social.
The Blue Discus, named after its disk body shape,
has grown in popularity over recent years thanks to
the wide range of color varieties available. Four
basic forms are known in the wild. The green form White Discus These fish will make a striking contrast, Blue Diamond Discus The darker markings on this
originates from the upper Amazon, while a brown housed alongside more colorful individuals, although fish are almost invisible; the blue coloration is intense
variety is found around Belem and Manaus, closer they are not very common. over the entire body.
to the river’s mouth. Reddish fish occur near the
Amazonian town of Alenquer, and a bluish strain These fish need a relatively tall tank, because of Once they are mature—by the time they are just
was discovered in the Rio Purus, Rio Manacapura, their body shape, and water conditions that mimic over 4 in (10 cm) in length—the females can be
and nearby lakes. Wild Heckel’s Discus from the Rio the blackwater environment that they naturally identified (on close examination) by the rounded
Negro is a separate species (Symphysodon discus), but inhabit. If kept in less-than-ideal conditions, they profile of the forehead, which has a more humped
commercially available forms may be hybrids are at risk from various diseases, including the appearance in the males. The genital area behind
developed in breeding programs with the Blue Discus. parasitic illness known as hole-in-the-head (see the long, thin pelvic fin is a further aid to sexing
p.58). Blue Discus are best housed as a group in a this species, since the male’s sperm duct is narrow
Turquoise Discus Much of the early development single-species setup, although this demands a large and triangular in shape, while the female’s egg-laying
of this variety was undertaken in Germany. The tank with efficient filtration, supported tube, or ovipositor, is broader and more rectangular
facial markings on each of these fish are unique. by regular partial water changes. in appearance.

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