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Discus Fish
All discus have the typical almost circular, discus-shape. They have
strong lateral compression and large anal and dorsal fins. The Discus has
a steep forehead and a small mouth. The iris of the eye is usually blood-red in color. The body and fin color and pattern varies greatly of the
species, habitat, and diet. For instance, the red tones are enhanced when
the fish is fed brine shrimp. In the vast Amazon basin, separate
populations have developed and originally created the differential of
color and markings.
Discus are found in calm parts of small, blackwater rivers, lakes, and
deep pools. They are usually found in small groups around submerged,
fallen trees; decaying wood and vegetation; and aquatic grasses. Discus
tend to stay in shaded areas during the day. The water is usually very
clean with little or no pollutants. Discus are widely distributed
throughout the Amazon Basin. The water in the natural habitat of Discus
is acidic, around a pH of 6.0-6.5; and is very soft, 0-3 dH. Discus are
found in warm water with a temperature of 77-84°F (25-29°C).
In Southeast Asia, Discus are raised in soft to medium hard, alkaline
water (3-9 dH, pH 7.0-8.0) with temperatures ranging from 81-91°F (27-33°C).
Discus prefer large, roomy, tall tanks of at least 40" (101 cm) long, and
20" (50 cm) high. The water should be clean and relatively bacteria free.
The tank should be arranged in dark colors and floating plants should be
used to diffuse the light. Discus may remain hidden all day if bright light
is used. Driftwood, roots, driftwood, and heavy vegetation should be
used to provide hiding places. Open swimming areas should be created.
A good filter for removing wastes is essential in Discus care. Partial
regular water changes are recommended to keep the Discus in top health.
They are very sensitive to pollutants, especially nitrates and nitrites.
Discus do best in peat-filtered water.
As a general rule, Discus should be kept in water with similar conditions
to their natural habitat. However, many Discus are raised in captivity and
their range of water conditions is more varied. Most Discus can tolerate
water with a pH of 5.0-7.5 and a water hardness of 0-8 dH. The water
should be kept warm, 77-86°F (25-30°C).
Discus are calm, timid fish who like to be kept in small groups of 6-8
fish. There is much debate to whether discus should be kept in
community tanks or in species tanks. Since Discus coexist with other
fish in nature, they can be kept with other peaceful fish. Discus feel
more comfortable if combined with small schooling fish such as
characins. When the discus see the characins in the open, they are likely
to come out, sensing that they are safe to swim. Adult Discus may eat
small fish if not brought up with small fish. Take care when combining
Discus with greedy feeders such as Angelfish, and Discus may not be
able to compete.
Some recommended species are Catfish (Loricarids, Corydoras ),
characins (tetras, hatchetfish, pencilfish), cichlids ( Apistogramma, Uaru
).
You will need to provide a large variety of live, dry, and frozen foods.
Try to feed Discus as many nutritional foods as possible such as fortified
flake foods, water insects, and brine shrimp. Some Discus are very picky
eaters and will only take live foods like Tubifex , bloodworms, mosquito
larvae, and beef heart. These foods are not especially healthy and should
only be used sparingly. Tubifex worms usually come from polluted
waterways and thus must be kept clean or the Discus may develop hole-in-the-head disease. Foods formulated for discus are available.
When sexing the Discus distinguishing the male and female is difficult.
Adult males may develop a small lump on their foreheads, but this
difference is not always reliable. During the spawning season, the shape
of the genital papillae serves as the best difference. It is round in female
and pointed in males, although this difference is also difficult to detect.
The best way to breed Discus is too raise a group of 6-8 fish and watch
to see them pair off at about 4" (10 cm). If a pair begins pecking of the
glass sides of the tank, it is ready to spawn. Remove this pair into a clean
tank with a pH of about 6.5, a water hardness of 1-3 dH, and a warm
water temperature of 82-88°F (28-31°C). The pair should be provided
with a vertical spawning medium, such as a large plastic tube, a large
rock, or a piece of slate. This surface will be carefully cleaned by the
pair. The female fans and guards the 100-200 eggs, while the male
guards the area. The eggs hatch in 2-3 days and the parents aide the
hatching fry by gently nibbling on the egg casings. The fry are then
moved by the parents to a different area where they are attached by
sticky filaments to this new site. After 4-5 days more, the fry attach
themselves to the flanks of the parents. The fry feed on a milky secretion
produced by gland cells in the parents skin. After about 10 days the fry
should be removed from the parents, or else the may overgraze and
damage the parent's skin. They should then be fed on Artemia nauplii.
Alternatively, discus larvae can be reared on commercial products if they
are removed just after hatching. Regular water changes are essential for
the survival of the young. The fry grow quickly and develop the discus-shape in 3-4 months.
In Southeast Asia, Discus are bred in medium hard, alkaline water.
Breeders keep young in buckets and perform complete water changes 2-4 times daily.
