Discus data sheet
German name:
discus
Scientific name:
Symphysodon aequifasciatus
Origin:
amazon
Size:
Body length up to 15 cm
Aquarium
Length:
Length from 150 cm width
Contents:
from 300 liters
water values
Temperature:
26°- 32° C
pH:
5 – 7
GH:
below 10° dH
Behave
Area:
lower area, near the ground
Lining:
Granules, dry food, frozen food (e.g. mosquito larvae, shrimp, brine shrimp and krill), live food (e.g. crustaceans), vegetables (e.g. peppers)
Behave:
very sociable, lives in swarms, can socialize with fish that move slowly, as the discus can become aggressive with fast movements
Number:
Schooling fish, at least 5 – 6 animals
Difficulty level:
Advanced H. cell, Symphysodon aequifasciatus – Karlsruhe Zoo 01, CC BY-SA 3.0
Aquariums suitable for discus
Discus cymbal Photo: Otto Baumann
The minimum number of discus that can or should be kept in a tank cannot be said in general terms. A group is of course better than 4 pieces. In a 160 x 80 x 60 tank, 6 to 8 discus and some other fish can be kept as company.
4 to 6 discus can be kept in an aquarium measuring 130 x 50 x 60 centimetres. At least 50 liters of water should be available per discus. Sometimes even 75 to 100 liters of water per discus are recommended.
In addition to the relatively high water pollution caused by discus excretions, territorial wars are problematic. If there is not enough space, individual fish will be suppressed. These animals are prone to disease.
Discus cymbal Photo: Otto Baumann
An aquarium for discus should be as high as possible. at z. B. 50 centimeters pool height, 10 centimeters for the bottom and 5 centimeters for the distance from the water level to the top edge can be deducted.
So there is only 35 centimeters of water depth left. A full-grown discus measuring 20 centimeters only has 7.5 cm of free swimming space above and below it. That’s very cramped.
An aquarium for discus must be at least 60 centimeters high and 50 centimeters deep.
Aquariums with a tank height of 75 centimeters are good and always have enough space.
Aquarium size for discus?
Discus with root © Calo Barranco
Discus can be kept in a 200 liter aquarium, but it is very small. 50 to 60 liters of water should be available for each individual animal. Because discus should be kept in a group of at least 6 to 8 animals, 200 liters is tight.
Some owners even assume that 80 to 100 liters of water should be available for each discus, otherwise problems are inevitable.
Breeders like to put a couple in 200 liters, but then the aquarium will be empty, without gravel, plants, furnishings and other fish.
In the interest of the fish, at least the recommendation of 50 to 60 liters per animal and a group size of 6 animals or more should be observed.
Keeping conditions for discus
Photo: Otto Baumann
Some aquarists already keep discus in tap water that is not too hard. This is said to be unproblematic if you don’t want to breed, if you feed a lot of frozen food and change the water frequently.
It is better to offer the animals conditions that are as species-appropriate as possible. The water for discus must be soft. Suitable is z. B. Osmosis water enriched with trace elements and humic substances. Clean rainwater is also suitable. Humic substances can be added with peat or TR7 from Dennerle. Tetra’s Torumin is less recommended because of the phosphate content.
The carbonate hardness can be even lower, e.g. B. 1 dKH. Not all plants tolerate such a low carbonate hardness. However, there are numerous plants that tolerate such values, so that even then no aquariums without plants are necessary.
Blue foam is sufficient as a filter medium.
There are different opinions and experiences about the recommended temperature.
The water must be kept clean by extensive water changes. The avoidance of rotting spots seems to be important, e.g. B. in the ground or by feeding.
Live food, frozen food and good granulated food are suitable as food.
socialization of discus
Discus (leopard) Photo: Otto Baumann
Mailed catfish are good company for discus. Armored catfish remain relatively small. They clear up leftovers of food that fall to the ground and do not snatch food from under the discus’ noses. However, some armored catfish species require cooler water than discus. Panda armored catfish are often socialized with discus.
Discus are omnivores. They sometimes eat fish larvae and the smallest young fish. However, Discus are not outright robbers. They tend to be peaceful or lazy. It is quite possible that in a discus tank z. B. tetras successfully multiply.
In warm water, however, the life expectancy of many fish species decreases, e.g. B. the red neon. Otocinclus do not like temperatures above 28° at all and rarely survive in the long term. In addition, discus are heavily harassed by Otocinclus, which practically graze discus skin.
Harlequin barbs are unusual as company, but fit surprisingly well.
Shrimp like to be eaten by discus. In some cases, however, shrimp are kept together with discus without any problems.
Do discus eat plants?
Normally discus do not eat plants. According to some reports, however, they nibble off fresh shoots from stem plants if they do not have enough plant food, e.g. B. Spirulina. Apparently, discus have a lack of botanicals, e.g. B. only get frozen food without green content for a long time. The deficiency is then satisfied on the plants. When they get green fodder again, they no longer eat the plants.
Can discus be kept in planted aquariums?
Discus (Leopard Snake Skin) Photo: Otto Baumann
Completely empty tanks can be seen again and again in pictures on the subject of discus. Apart from water, a spawning cone and the fish, there is nothing in the tank. Some discus keepers do not add substrate to the tank and keep plants in flower pots.
This is only for hygienic reasons. In such a Breeding Cube it is much easier to reconcile the need for food and good water quality. Targeted feeding of the young fish in the first few weeks is very important and cannot be done optimally in a densely planted tank.
However, substrate can be used. Even a few roots and a few plants do not bother.
Compromises are always necessary in the plant tank. A temperature of 30°, acidic water and the excretions of the fish are very difficult to reconcile with some plants.
Nevertheless, there are enough plants that are suitable for discus tanks. Various ferns, Amazon sword plants and cryptocorynes do well in such conditions.
It is sometimes said that discus in heavily planted aquariums are subject to social stress and are susceptible to bacteria and parasites.
Photo: Otto Baumann
However, healthy fish with a varied diet can stand up to bacteria and parasites in the best possible way. Most importantly, heavily planted tanks do not produce more threatening bacteria and parasites than unplanted tanks. Such statements are probably a misinterpretation.
Planted tanks often only offer one free space, which then corresponds to a territory. The room rich in hiding places then offers numerous retreat possibilities for oppressed discus.
A suppressed disc that can successfully and permanently hide will wither away over time. The animals have to face their competitors and should live out their food envy when feeding.
Ideally, the aggression is evenly distributed among all animals. The aggression must not be concentrated on one animal.
Nevertheless, discus can also be kept in a densely planted tank. However, it should then be possible to accommodate resigned discus in a second tank. The long-term care of discus fish in a display tank without alternative options is daring.
Many discus keepers keep their discus in planted aquariums. Tanks without substrate and plants are only used for breeding.
Photo: Otto Baumann
The amount of plants is not as important as the type of planting. Discus like to withdraw between long-stemmed plants. They often stand covered between the plants and observe what the owner is doing in front of the aquarium.
Nevertheless, sufficient swimming space must be available. Tiger lotus are also suitable plants. The large leaves darken the tank, which discus likes. Because of the long stems, there is enough swimming space for the discus even with good planting.
However, too much planting in a discus tank does not make sense. Feeding and cleaning is made more difficult. In addition, a heavily planted tank does not correspond to the discus’ natural biotope. Too much planting also requires a lot of care interventions, which bring unrest to the aquarium.
Always carry out water changes with tempered water.
Discus do not tolerate major temperature fluctuations. The best thing is an automatic water change that takes place over a longer period of time. In any case, when changing the water, the water must run slowly, or only a small amount of water is changed every day.
Water from the hot water tap may only be used for tempering if no copper can get into the water.
Osmosis water and discus
Can discus be kept in pure reverse osmosis water?
Adult discus obviously feel comfortable in pure osmosis water that is enriched with trace elements at most. In most cases, the carbonate hardness is less than 0.5. The pH should be around 6. It is often claimed in the literature that discus can be held in hard water without any problems. Some owners confirm this experience. Other owners disagree.
Such water is not suitable for rearing young discus. With pure osmosis water, the young always lagged behind in growth. Even if the water is enriched with trace elements. The cause may lie in the composition of the trace elements. However, it is not known which factor is decisive. Apparently there is no preparation that has the right composition. Increasing the trace element concentration in the feed does not seem to help either.
Young are best raised in non-polluted water with a total hardness below 10 and a low nitrate content. Nitrate is the number one growth inhibitor. The nitrate level is best kept at a constantly low level in a flow-through aquarium.
Breeding farms change 50-100% water daily.
discus and aggressiveness
Discus form a hierarchy and defend their territories.
Symphysodon discus Source: Image on Wikimedia Commons License: CC Attr. 3.0 Author: Doronenko
Discus fish often form a peaceful coexisting shoal in the retailer’s tank because they feel more comfortable together when conditions are otherwise inadequate. When they later feel comfortable in their home aquarium,…