|KEEPING DISCUS SA STYLE
This is an exercise in
information sharing and
promotion of keeping freshwater fishes in home aquaria.
The notes given on this site for general fish keeping are repeated
here with the needs of Discus
I hope that my experiences help
you enjoy your
aquaculture adventures. The example given is from my experience
keeping Discus. The same principles apply for all fishes: correct
size tank, correct water conditions, suitable filtration, appropriate
and habitat provisions, and, of course, proper feeding and maintenance.
Discus are native to the
Amazon Basin, living
in the "black water" rivers of the Amazon River system. There is
a wide variety of colour types, bred from the wild species, Symphysodon
aequifasciata and S. discus.
Success with keeping Discus
species and hybrids
is possible in South Australia, even with our hard waters and our
from the Amazon Basin. Of course, it is important to pay close
to providing a suitable, quiet aquarium habitat that has the parameters
that are listed below. While not trying to duplicate the water
of the Amazon, a sustainable environment can be set up.
It is essential to
understand the water chemistry
involved in keeping aquaria for Discus, with special attention
paid to water hardness and levels of acidity. The trick is to
low levels of oxygen and have tanks water free of ammonia and
Nitrate levels must also be low.
CONDITIONS FOR KEEPING DISCUS
UP AN AQUARIUM OF DISCUS FISH: an explanation of the
amble room- a 150 litre
tank that is 45 to 50 cms deep is OK for a mature pair; plan ahead if
wish to breed Discus.
a warm temperature-
between 25o and 27o Celsius for general keeping
30o-32o C for breeding; Discus require warm water
for healthy metabolism.
adequate lighting- I
have found either a fluorescent "Power Glo" Enhanced Spectrum
of 40 watts is good with Discus in a well, planted aquarium; & a
Glo" Daylight spectrum provides good lighting above breeding tanks.
clean, soft water of low
for general keeping, a General Hardness between 10-15 dGH, Carbonate
6-8 dKH and pH between 6.5 and 6.8 (slightly acidic) is ideal; for
purposes, maintainingwater of low mineral content is essential,
3 - 10 dGH, and 0 - 3 dKH and a pH 6.0 - 6.8; DON'T
USE RAIN WATER as it may be contaminated with industrial
fallout or poisons from agricultural spray drift.
frequent partial water
changes- a powered driven under
biological filter, paired with a canister type filter, works well for
in the main, holding tank. Breeding tanks require very efficient
very mild water movement
and perhaps some gentle aeration to assist gaseous exchange and to
temperature layering in the tank; and
a quiet location for
the aquarium, away from vibrations and household traffic. Discus
will take fright easily if there is movement above them so the optimum
height for the base of the tank above the floor is at human chest
definitely do not place Discus tanks at floor level if there is
movement in the room.
Keeping Discus is more
about keeping an efficient
biological filter working and maintaining good water quality than
GETTING THE WATER RIGHT IS
ESSENTIAL BUT NOT
DIFFICULT TO ACHIEVE
The best advice is
to buy the biggest tank that you can afford (but no smaller than
a 150 litre capacity) and at least 45 cms deep. Fill
with moderately soft water that is slightly acidic (see
I use a well planted tank for general keeping. However, breeding
pairs of Discus are best kept in an almost bare tank fitted for
the purpose with a potted plant (such as a large Amazon Sword Plant, Echinodorus
blecheri) and an upturned, sterilized terra cotta pot (cover the
or a PVC "breeding pole" or a slate slab for attaching the eggs and an
efficient, external filter, with the flow pipes fitted with a sponge
to dampen the water flow & to prevent fry from being sucked in!
Discus have a low tolerance of
and nitrites. Ammonia is a soluble gas which in water takes two
ammonia(NH3) and ammonium (NH4+).
The pH of the water determines the form that is present, with ammonia
present in water with a pH over 7.0 (basic) and ammonium is present in
water of pH less than 7.0 (acidic). Both are toxic to fishes and
ammonia is highly toxic. In the pH range at which Discus are kept
(acidic) the danger from ammonia poisoning is not problematic and
ammonium levels are best kept close to zero.
Water Chemistry: read this background material for an
to water chemistry.
Most South Australian tap water is
and has a high pH and high conductivity because of its dissolved
content. Our River Murray water in S. A. is especially heavily
with salts and pollutants. Those people lucky enough to receive
from the Myponga Reservoir are able to use tap water that is suitable
Discus keeping, however, other people will need to treat their tap
to make it suitable for Discus.
Discus require soft water that has
a low mineral
content and low conductivity and is
acidic (pH 6.0 - 6.8) and is pollutant free. This can be achieved
by mixing dechloraminated tap water with water treated through a
osmosis unit (RO water), to achieve a soft water that has some trace
and the required pH and Hardness but no chlorine or chloramines.
Testing the water to check the General Hardness (dGH) and pH is
and can be done adequately with test kits sold at most pet shops or
and fish suppliers. Aim to achieve a General Hardness between 10o-15o
dGH, a Carbonate Hardness (dKH) of < 3.0 and pH between 6.5
6.8 for a display tank. TEST THE WATER BEFORE
IT, to determine pH and Hardness.
Using RO water requires
close attention to providing the necessary trace elements, hence my use
of dechloraminated tap water mixed with RO water. Using RO water
requires careful monitoring of pH levels to avoid extreme acidity. BE
as SA tap water is heavily chlorinated or chloraminated at the point of
supply and, in that condition, it is fatal to discus fish and
some RO membranes. Check the RO membrane type with a reputable
to assure that it is not affected by chlorine.
Dechloraminated Tap Water
is made by treating tap water with Wardley's "Tri-Start" or Biotec's
Ager Cn" or similar products, to remove the chlorine and
Letting the water stand before using will remove free chlorine
A serious aquarist will prepare a large volume of tap water by treating
it to remove chlorine and chloramines and letting it stand before
it to an aquarium. Filtration through activated carbon will
most other contaminants in tap water. Boiling also reduces some
content and sterilizes the water (but is impractical on a large scale!).
Preparing water for use
is advisable prior to using it for water changes. A reservoir
is a good idea; set up to have enough water for your expected water
always on hand and dechloraminated and pH and hardness adjusted for use.
is done quickly, by using chemical additives. Sodium
(baking soda or bicarbonate of soda NOT baking powder) is used to
the pH upwards. Sodium bicarbonate does not act as
to prevent further pH drop occurring. Adding dolomite,
sand, or oyster shells to the filter medium help buffer pH
Reducing pH is not an easy
matter, as water
with a high pH is usually hard, high in alkalinity and well
Lowering the pH requires adjusting the hardness and
levels first. Mixing water that has been softened by running it through
a water softener could result in water with a desired pH.
Running peat in the filter will also lower pH (and colour the
like tea) and mixing rain water with hard tap water may reduce pH.
Adding phosphoric acid (food grade) or hydrochloric acid also
the pH. Add these chemicals in very small amounts
test the water frequently until the desired pH is reached.
Commercial products such as pH UP and pH Down are
from stockists. Purchase one that has a buffering characteristic,
if your tank water is prone to rapid changes in pH.
Using acidic, mineral depleted waters (soft water, as
required for Discus)
can be prone to rapid drops in pH due to acidification during
bio-filtration process. Using a good acid buffer is
Consult your stockist.
I have found that in the general
keeping tanks, not
the breeding tanks, a combination of an under gravel filter and an
canister filter serves well for display tanks. Internal filters
also effective but they require more regular cleaning and can be
Consult your local aquarium shop for advice on the range of types
(it is huge- so do your research first). A single breeding tank
be serviced with an external filter or an internal sponge filter.
arrays of tanks are usually linked to a common, filtering system
mechanical and biological filtration units or fluid bed filters.
Discus require water with no nitrites or ammonia, as in a very
biological filtering system. Frequent, partial water changes are
also essential as part of the water management routine, with bi-weekly
changes of 20% being minimal to remove the nitrates produced by the
filter. A well functioning filtration system will take about six
months to mature the biological filtration component.
ON THE TYPE OF FILTRATION
TO BE USED
cannot have too much filtration!
Begin with the best system that you can afford. Beginners
recommended to first Read: UNDERSTANDING
ADDING SUBSTRATE, ROCKS and
environmentally conscious and do not plunder the landscape to obtain
sand, rocks and wood!
If the choice is not to house
a bare tank, gravel and sand are the best substrate materials. If
an external filter is used, the gravel layers must be thin (no more
20 - 30 mm) and regularly cleaned when siphoning out accumulated
The sand or gravel depth will need to be at least 20 mm in the front of
the tank, grading to 30 mm at the back (with the slope providing a fall
of the detritus to the front for easier cleaning later on).
The darker the material, the better, as it reflects less light into the
fish's eyes as they forage. Most commercially available material
in S. A. is too light in colour and needs to be shaded by plants and
Shops usually sell what they can get, not what you need, and that is
by availability and commercial practices. Do not use limestone,
or dolomite gravels or sands. Choose quarried, alluvial quartz
has rounded grains), river or creek sands and gravels that are not
or heavily mineralised with iron or calcium. Again, consult your
local supplier, who may stock a number of different substrate materials
or obtain them for you on request. Wash the sand very thoroughly to
any dust, silt, clay or humus particles that you have purchased as
along with the substrate material.
Using an under gravel filter will
decide the grain
size used. Fine, pea gravel is best for an under gravel filter,
to a thickness of 50 to 80 mm.
(if used) also
need to be smooth edged and of non calcareous rocks (no limestone,
or marl) and not highly mineralised. S. A. offers a nice range of
local granites, basalts, slates, quartzites and sandstones that are
Creek bed rocks may be suitable but please do not rob the environment
furnish your tanks. Make sure the rocks have no sharp edges
and wash them thoroughly. Arrange the rocks so as they will not
or move or create traps for the fish. Rocks are not
to a Discus tank, but are used for decor and to provide hiding places
the other fish in large, community tanks.
As wild Discus take refuge among
the roots of
trees at the water's edge, WOOD can be used as decor for aquariums
seasoned oak and beech are suitable). However, S. A. offers
little material that is suitable. River Red Gum (Eucalyptus
wood, that has been long dead and well aged, soaked and boiled, is
Imported peat "logs" and mangrove roots are available and need to be
washed before using them. Using wood may stain the water with
and other dyes (as in the Amazon itself!) and also add to the
of the water. Any strong discolouration may be removed by using
activated carbon-filter but this is not essential, as Discus thrive in
such "black" waters. Moulded plastic replications of "Amazon"
landscapes are available from some aquarium shops and give a wood-like
appearance, with low environmental impact.
Always treat any wood before using
it, so that
any tannins are removed from the timber. Soak the wood in a large
tub of water until it no longer discolours the water. Repeated
and boiling may make this job quicker, if practical, changing the water
between successive soaking, boiling and cooling, until the water is not
I DO NOT use painted stones or
shells or metal ornaments. Coral and shells trap food particles
pollute easily. Processed items may contain heavy metals in the
or ceramic fabric that may contaminate. Safe, moulded plastic
decor is available from some aquarium shops- but check to see if it is
labelled "safe". I prefer a "natural looking" tank environment
I do not use ornaments. It is a not merely a matter of taste, as
we can never be sure what paints and dyes have been used in colouring
mouldings and coral.
add a great
deal of interest and beauty to the tank- and also increase the
demand on the water and filter. I suggest using plants from the
Basin and Asia that have been cultivated for aquarium use.
Amazon Swords (Echinodorus species)
choices planted directly into the substrate or into pots.
Java Fern (Microsorum
needs to be
attached to the rocks or wood and not planted in the substrate.
Dwarf Anubias (Anubias
nana) can also
be tied to rocks with nylon fishing line.
Thin Vallisneria (Vallisneria
will colonise a sandy substrate.
Cryps (Cryptocoryne species)
are also useful
. Plant Cryps in the foreground of the tank.
Species of Bacopa, Cabomba,
Hygrophyla and Ludwigia are also recommended but will grow
lanky in the warm conditions of a Discus tank.
Discus do better if kept in
"AGEING" THE AQUARIUM WATER is
good practice, as it allows for cleaner water and less introduced
Let dechloraminated water stand in a special tank for ageing the
When a new tank is established, never introduce any Discus until a
water ageing treatment has been used or until the water has stood to
for about a month. Set the tank in place, with its substrata,
and plants installed. Run the heater, filter and lighting as
Add some bio-starting preparations to get the biological filter
I use "BIO SUPER CONCENTRATE" (made by Biotec), Hagen's "Cycle" &
Control" or Rudduck's "Pura-Water" to add the right aerobic bacteria
enzymes to establish the biodegrading functions in the tank. This
is safer than inoculating the tank from an established one, as it
the risk of introducing pathogens, but, at a pinch, a new tank can have
water and gravel from a well running tank added to kick-start the
processes. It is necessary to wait a month for a new
tank to "age" as the development of ammonia and nitrites begins
the tank is filled and planted (that is, as soon as a "biological load"
is added to the water) and peaks at about the second week.
the ammonia, nitrite, pH and hardness levels. Increase the
load gradually by introducing the fish in small numbers.
Discus are intolerant of
high levels of
and nitrite in the water (as are all fishes!), so let the tank water
Testing the water for nitrite (NO2)
is essential practice. Excessive ammonia levels may be controlled by
Biotec's "Amrite Down" solutions or Aqua Master's "AMMO-EX" grannules
the filtration medium (in box, canister of trickle filters only).
Purchase a simple nitrite testing kit and test daily until the nitrite
levels stabilise at undetectable amounts. I test for pH
nitrite levels daily when setting up a new tank for Discus.
After a month, weekly testing is adequate for maintenance. The
(notice 'nitrates' NO3,
'nitrites' NO2) that
produced as the end product of an efficient, biological filtration
will be absorbed by plants to some degree, but frequent, partial water
changes are necessary to control the nitrate levels in most cases.
Using Peat as a water conditioner
Add clean German peat to the canister or external filter system, to
the dyed, tea-coloured water that approximates the tannin and humus
waters of the natural habitat of Discus. Filtration
peat also reduces the pH. Alternatively, conditioning with
Tetra "Blackwater Extract" is also helpful. Filtration through
carbon will remove the tannin and other dyes, so peat filtration is not
used with carbon filters.
For an Amazon
After the tank has been running for a
add a pair of Dwarf Gouramis (Colisa lalia) to provide wastes
will "feed" the biological system in the tank. After
week add ten to twenty Cardinal Tetra (Paracheirodon axelrodi)
ten Lemon Tetras (Hyphessobrycon pulchripinnis) to further
the biological loading of the tank. These fishes can make
companion fish to Discus, as they share the same soft water
as Discus and are quiet types that will not bother Discus.
I have found Cardinal Tetras and
other small Tetras,
Dwarf Gouramis (Colisa lalia), Rams (Papiliochromis ramirezi)
and small Clown Loaches (Botia macracantha) to be
for adult Discus. However, there is danger in keeping
Angel Fish (Pterophyllum scalare and hybrids) and Cory Cats (Corydorus
sp.) with Discus, as they may carry internal parasites that
Discus badly. If thorough quarantine procedures are followed,
Cats are useful in cleaning up uneaten food, however. Large
are usually too competitive at feed time to be kept with Discus,
and are best in a tank of their own. Discus are slow easily
from eating by boisterous fishes, so it is best to house them on their
Add the Discus about a
week later (i.e.
two weeks from setting up), when all the plants are established and the
tank is crystal clear and aged (looks slightly yellow and has a
population of aerobic bacteria- indicated by no detectable ammonium or
nitrite levels when tested). As Discus can be kept
Dwarf Gouramis and a school of Cardinal Tetras to good effect, it is
necessary to remove any fish that may disturb the Discus.
Be sure to check the water conditions are suitable for Discus by
it for pH, hardness and nitrite. Gradually transfer the fish to the new
tank by allowing the plastic bag, in which you carry the fish home, to
float in the tank to adjust to the water temperature before releasing
fish. Do this over a twenty minute period then gradually
water from the tank to the bag of fish, in small amounts, to adjust the
other water conditions. This procedure will lessen the shock of
pH and Hardness changes on the fish.
For a Discus
Set up the tank as desired and let it
a week, with heaters, lights and filters turned on. If well aged
water is not available, then add three Discus to start, transferring
as described above. Monitor the water chemistry using at least a
pH test kit, an ammonia/ammonium test kit and a nitrite test kit.
Perform daily partial water changes (20%) for the next two
or until the ammonium and nitrite levels are safe. Use a
additive such as "Cycle" to boost the biological functions until a zero
reading of nitrite is obtained. Add to the biological
Discus are best kept on their own, if
is to be attempted or a purist approach is desired.
Planting the tank makes a natural
for general housing of Discus. Some breeders report that there is
less chance of Discus developing head and lateral-line erosion ("hole
the head" disease) when kept in a well planted aquarium. Being
Discus will nibble at soft plants and perhaps that gives a diet that
from HLE. I particularly like to use Water Wisteria, Java Fern
Amazon Sword Plants in a fairly dense planting to show the fish to
The use of CO2 boosters in planted
is recommended. The temperatures at which Discus are kept do not
allow for high concentrations of dissolved gases (oxygen or carbon
and the addition of CO2 aids plant growth. The
of the tank decor depends on the space available (allow some for the
It can consist of non-calcareous rocks, old mangrove roots or drift
pieces that have been cleaned, boiled and fitted into the
Using plants adds to the biological loading of the tank and care must
taken to prevent overloading as well as checking pollution.
dead and shed leaves to prevent fouling of the water from decaying
matter. Discus love places in which to hide and they look good
about among the plants. When plants are used, gentle aeration is
essential, especially at night, to remove excess CO2 from
Once the Discus are established in
the tank, continue
to test pH levels and for ammonia and for nitrite levels and change
1/3 of the water every week or 1/5 every two days to control nitrate
Watch for any "bloom" of bacteria that may occur (shown as a white
of the water and a white coating on the interior of the glass) or for
of the aerobic bacteria in the filter (indicated by an increase in
and nitrite levels). Bloom can be reduced with partial water
and minor adjustments can be made by using Rudduck's "Pura-Water" or
"Amrite Down" or a similar product. This is usually not necessary
unless major water changes are made or the biological filter is not
properly. Remember, it takes six months for a biological filter
function at optimum levels of efficiency.
It cannot be stressed too much,
Discus culture requires very clean and well conditioned water and
Frequent partial water changes are essential practice. Avoid
changes in water, unless you are prepared to start over again as with a
new tank. Always use dechloraminated water adjusted to the
temperature, pH and hardness of the tank water.