Care and Breeding Basic
More has been written about the Discus than any other tropical fish in
the last 50 years, and it is now one of the most popular cichlids in the
hobby, with many books devoted to it. This is intended to be a very brief
general guide to its keeping and breeding within the aquarium.
When wild caught discus were
first introduced into the hobby many years ago, they were a rare site,
and thought very hard to keep. With time, experienced hobbyists mastered
this aspect and the next step was breeding. Slowly people managed to get
eggs, but they would never get successful fry. They key was leaving the
fry with the parents, from whom they graze, eating their highly nutritious
slime coating. Now discus breeding is common place, any thousands of colour
strains have been produced, in addition to the many wild colour forms.
Discus are most commonly found in dense planting and wooded areas in slow
moving rivers and backwaters in the Amazon river system. These waters
are soft, warm and acidic, with little current. Their natural flat shape
and colour pattern is designed to give camouflage in their natural home.
They can usually be found in large groups, and when not spawning are mostly
a social cichlids. Their natural food is comprised of aquatic inverts,
insects, small fish and fry and any other naturally occurring food that
may be available. Many other commonly kept south American tetras and cichlids
can be found in these waters.
TEMPRAMENT, BEHAVIOR AND
In case you need reminding, Discus are Cichlids! In the real world this
means they are fishes of changeable behaviour, but also of character and
personality. They can on occasion be aggressive towards their own kind
and others, mainly when pair bonds are formed, or when territory of fry
are involved. If some consideration is paid to this, in cichlid terms
they are generally quite mild in behaviour.
The main problem is with bullying
within themselves. Often, in small groups of fish the individual at the
bottom of the pecking order is on the receiving end of a great deal of
bullying, which can result in death. To avoid this, I would advocate not
keeping the fish in groups of less than 4, with 6+ being an optimum, especially
when young. This seems to spread the bullying out, and also increase the
confidence of the fish.
Size wise, roughly 6-8"
round is a good side for an adult discus.
This is one of the areas that gives rise to the greatest amount of arguments
between discus keepers, but this is what I feel is a good basic guide
- Water conditions for general keeping
: pH 5.8-7.4 with 6.3-6.9 an optimum for most varieties. Water hardness
is just as important as pH, a kH of 1-6 and gH of 2-11 being generally
suitable. The fish may live in harder water, but for long term they
need soft to medium water to thrive.
- Temperature : a range of 80-84 is acceptable,
although many fish keepers use higher temperatures of up to 90f.
- Water quality : The higher the quality,
the better! Tanks must be mature and stable, with 0 ammonia / nitrite,
and nitrates and DOC's as low as possible, with 20ppm an upper limit.
Trying to keep the water as free of metals, phosphates and other contaminants
will also help. Large weekly water changes are probably the order of
- Filtration: Being big messy cichlids,
efficient biological filtration is needed, but filtration that doesn't
produce too much current.
- Tank size : There are 2 main requirements,
tank depth and volume. Because of their size and swimming habits, a
minimum of 18" is needed for tank depth, with deeper being better.
Volume wise, a rough guide is that each adult discus will need 10 gallons
of water. Larger tanks will also give more stable water conditions,
and taking into account other considerations the minimum size for a
discus display tank should be roughly 40 gallons.
- Feeding : A varied diet is the order of
the day, this may include a high quality dried food up to about 50-60%
maximum, which the discus will take with greed. Other foods should be
insect fish based, such as frozen brine shrimp, blood worm, mysis shrimp,
black mosquito larvae, chopped earth worm, prawns, chopped cockle etc.
Discus can be susceptible to internal parasitic infections, so take
care with live foods, and due to the fats / proteins its perhaps best
to feed animal meant sparingly if at all.
- Tank mates : tank mates should be none
aggressive fish that are not too active or skittish, and will tolerate
warm soft acidic water. Dwarf south American cichlids, sucker mouth
catfish, cory's, tetras, rasboras, pencil fish among others will provide
good friends for discus. Shoals of tetras or similar will act as dither
fish, making the discus feel more safe in their surroundings
- Tank Set-up : Discus certainly don't require
bare tanks, and furnished display aquarium may even be advantageous.
Tall planting round the back and sides of the tank, together with an
inert substrate will limit the skittish behaviour of the fish. Bog wood
and perhaps a little inert rock work will also be accepted, but the
fish should be left large open swimming areas in the tank centre
Once many keepers have mastered keeping discus, their attentions often
turn to breeding. While not being impossible, it can be hard work, but
is also greatly rewarding. Like all cichlids, discus choose a spawning
site then guard and rear the eggs and resulting fry.
- Sexing : Discus can be very hard to sex
other than when spawning, and no reliable methods exist. A guide may
be that males have longer fin extensions and a wider fore head.
- Pairing: Discus don't take well to arranged
marriages, so the best way to get a breeding pair in general is to by
a group of young unrelated fish of the same colour type and let them
pair up themselves. This may happen from when the fish are half grown,
but generally spawning doesn't start until the fish are roughly ¾
of their adult size. Once a pair is formed it will often remain for
the life of the fish
- Spawning : Discus choose a near vertical
smooth spawning site, which is cleaned before 80-400 eggs are laid by
the female, and fertilised by the male. It takes 50-60 hours for the
eggs to hatch, and another 36-48 hours for them to become free swimming,
at which point the fry will start to graze of their parents. It may
often take a few attempts for the pair to get it right, but two females
can lay eggs and appear to be a pair.
- Breeding Tank : Breeding tanks are best
kept simple, with simple air powered filtration, spawning sites (terracotta
cones, broad leafed plants or slate) and no substrate. Water should
be very soft to allow the eggs to develop properly, with excellent water
quality and a temperature of about 84-88f. The tank need not be as large
as the display tanks, but something of the order of 24x18x18 is certainly
- Feeding and conditioning : The parents
will need a good and varied diet not just to condition them to spawn,
but to provide nutrition when they are feeding their fry. Large water
changes, a temperature rise and heavy feeding is often a good spawning
- Fry rearing: The fry do best when given
additional feedings of small foods whilst with the parents, such as
baby brine shrimp. After 3-6 weeks, the parents will be exhausted, and
the fry growing fast so it is best to remove them. This is where lots
of tanks and water changes are needed to achieve a decent growth rate.
I used to grow circa. 40 fry to just under 2" in a 55G tank, and
this required heavy water changing. The discus market is saturated with
fish, so it best to grow 20-50 excellent fry than 80 runts. Growth is
reasonable, but not spectacular.
Although this is just a fraction
of the information available, I hope it of help in some way. Enjoy the
King of the Aquarium!
Picture and article by Chris