- Family: Chichlidae
- Scientific Name: Symphysodon
- Care level: Challenging
- Temperament: Peaceful and shy
- Diet: Omnivorous
- Water conditions: Slightly acidic, very warm
- Max Size: Up to ten inches
- Minimum tank size (as adult): 50 gallons
Brief Overview: Discus Fish Care
The discus fish is a brightly-colored, uniquely-shaped fish native to the Amazon river basin in South America. These are popular choices for freshwater aquariums, sporting vibrant colors and an oblong shape that can spruce up even the most boring fish hobbyist’s living room. They are often referred to synonymously as pompadour fish.
Because these fish tend to live in isolated tributaries of the Amazon, where floodwaters create rapidly changing habitats from season to season, there is limited migration of isolated populations. As a result, there are interesting features present in certain isolated groups of discus fish.
Discus Fish Appearance
Discus fish have a body shape that seems flattened, with a rounded overall shape similar to that of a discus. The fish has bright patterns of green, blue, red, and brown, with other variants existing as the result of selective breeding in aquariums. They normally reach up to six inches in length, but healthy, unthreatened fish living in captivity can grown even larger.
There is no sexual dimorphism for this fish – meaning males and females look practically identical. However, males tend to grow to a larger size than do females. Females may have coloring that is more pronounced in some cases, but this is usually not noticeable.
While there are really only three different genetic types of discus fish, there are dozens of colors and patterns available. These include the Albino White Snake, the Leopard Skin, the Super Red turquoise, and the Super Red Melon, just to name a few.
What size are discus when they’re small?
Discus fish start off very tiny, about one or two inches in length. Although they aren’t terribly long, you need to remember that discus fish tend to be as tall as they are long, giving them a blockier appearance and causing them to take up more room in your tank.
How fast/slow should you expect them to grow?
Discus fish can live for ten years or more. They grow rapidly for the first few months, gaining up to an inch per month for the first three months. After this time, their growth will level off, with larger fish becoming so huge only in the later years of their lives. Interestingly, discus fish tend to grow fastest in smaller tanks.
What’s their max size?
The maximum size ever recorded for a wild discus is around six inches, but aquarium hobbyists report that these fish can grow as long as nine inches by providing optimal conditions. You can help your discus reach a large size by provided frequent water changes during critical growth periods.
Different types of discus fish
There are three different types of scientifically recognized discus fish. While other subspecies have been proposed and several variants have been achieved by selective breeding in captivity, only three major natural types are recognized, based on their coloring and genetic makeup. They are as follows.
- Symphysodon aequifasciatus (Blue or brown discus)
- Symphysodon discus (Red discus, also known as Heckel discus)
- Symphysodon tarzoo (Green discus)
Discus Fish Diet & Feeding
What do discus fish eat in the wild?
In the wild, discus fish eat a varied diet consisting of plant material (sch as algae and detritus) and small invertebrates. They tend to eat more invertebrates during the high-water season. Discus fish will also eat zooplankton and other small insects.
Discus Fish Feeding habits
You can feed your discus fish live or frozen feed. Tubifex, brine shrimp, corethra, gammarus, and blood worm are all popular foods. You can also use foods like prawns, mussels, nettle, vegetables, which are other common choices. Artificial feeds, like spirulina or supplements, can also be fed.
These fish can be challenging to feed, because they tend to stay in a corner of the tank while other fish feed. Therefore, it can be difficult to keep this fish in the same tank as others, since it will not feed when others are present.
Furthermore, because a discus fish’s food is so protein-rich, it is not uncommon for protein-rich leftovers to sink to the bottom of the tank and cause a buildup of ammonia and nitrates. This will require more diligent cleaning.
What foods are recommended for discus fish?
Feed your discus fish a varied diet of processed and frozen live foods. Granules tend to be the best option, as discus don’t like to feed at the surface and will instead feed at the middle of the tank. You can also supplement with bloodworms in a feeder cone. Blackworms are also a good choice, but these should be fed sparingly, as they can harbor parasites. As a special treat, you can even feed your discus frozen beef heart – just make sure you clean your tank after feeding this food, as it can cause pollution.
Discus Fish Tank Setup
Brief overview of natural habitat
Discus fish are naturally found in the floodplain lakes and rivers of the lowland Amazon basin. This geographic area changes vastly during the course of a year – the rainy season in December promotes flooding, as tropical showers and ice water increase water levels. As a result, tributaries will change their streamline, inundating crystal-clear waters with mud and clay. The surrounding area then turns into a bog.
After this time has passed, the water level decreases, and blackwater appears. This blackwater occurs among riversides, and consists of rotting plant matter and other detritus. Discus fish love places with plenty of hiding places.
As a result, they usually live in blackwater habitats, preferring areas like flooded forests and floodplains. This provides them with plenty of coverage and detritus upon which to feed. They tend to stay away from main river channels and instead hang out in slow-moving tributaries and forest pools. In these areas, the fish lives in schools and gathers in sheltered areas, such as those around tree roots and rocks.
Their range naturally extends down the Rio Solimoes and along the main Amazon river, occupying countries such as Colombia, Peru, Brazil, Guyana, and Suriname.
Discus Tank Size
While discus only tend to grow to around six inches, they can grow to be just about as tall as they are long, meaning a large aquarium is necessary. In addition, these fish don’t like to be overcrowded, but do like to school, meaning you will need to provide plenty of room for other fish to spread out.
Consider a tank offering a capacity of at least fifty gallons. If you keep more than one fish, you will need an even larger capacity. These fish are much taller than other fish, so keep your proportions in mind when you are selecting a tank. You need a tank that is long, but also very high. It can be very difficult to acclimate your discus fish to its tank. Relocating the fish causes extensive stress. Plan your movements accordingly to help reduce the amount of stress your discus suffers in transit.
Discus fish are very sensitive to water quality, so a powerful canister filter is something I recommend. They will also need to have the bottom substrate of their tanks regularly siphoned out, and their water renewed partially at least once a week.
Discus fish prefer tank water that is soft and slightly acidic. The ideal pH is between 6.0 and 6.5. Warm water is required, with ideal temperatures ranging from eighty to ninety degrees Fahrenheit. Try to avoid putting substrate at the bottom of the tank to avoid getting your fish sick, but you can add some minimal bottom material if necessary.
Discus fish are very shy, meaning you should opt for a heavily planted tank. Lots of rocks, decorations, and driftwood provide places for your fish to hide. This coverage will help make them feel comfortable inside the tank. It can be challenging to maintain a planted tank when you consider the warm temperatures needed for discus fish, so you might have trouble keeping plants alive. You might consider plants like Didiplis diandra Rotala Indica, and Vallisneria.
While it’s a good idea to house discus in a planted tank, you can also house them in a bare-bottomed tank. This is not as aesthetically pleasing, but does prevent the buildup of substrate so that you can clean out feces and rotting debris more easily. This will help to preserve your water quality.
Discus Fish Tank Mates
Discus fish are very social, tending to occur in large groups with several dozen individuals. During breeding, mating pairs move away from the group to avoid cannibalism of the young. They tend to be very shy, and don’t like loud noises or sudden movements. Restless, highly active tank mates are also disruptive to this fish species.
Discus Fish Tank Mates
Discus fish are very shy and good-natured. They are not predators and, unlike other cichlids, don’t dig up tank substrate. They are schooling fish, so like to be in groups of at least six species. Never house a discus fish by itself.
The main challenge in housing a discus fish with other species is that it eats slowly and lives in warm waters. This can be challenging for other fish to deal with. They are not compatible with aggressive fish, either.
What follows is a list of the fish species with which discus fish cohabitate well, although the list is by no means comprehensive.
- Clown loach
- Rummy nose tetra
- Cardinal tetra
- Ram cichlid
- Neon tetra
How to Keep Discus Fish Healthy
Discus fish are not subject to many diseases, but some care is necessary in ensuring they remain healthy when exposed to other tropical aquarium fish. Like most captive fish, they are susceptible to things like parasites, fungi, and bacteria. All discus fish should be quarantined before being introduced to a new tank to help reduce the likelihood of infection.
Common diseases to look out for:
The most common discus diseases are related to poor water quality. By exercising good sanitation and cleaning your tank’s water regularly, you won’t to worry too much about this being a concern with your fish.
One of the most common symptoms of disease among discus fish is flicking (or scratching and clamped fins). You will notice them rubbing their fins against rocks, and they will experience rapid breathing and red skin. This is almost always caused by an ectoparasitic infestation. It can be treated by changing out the water and wiping down the sides of the aquarium. You can treat with a de-wormer and by adding aquatic salt.
Nitrite poisoning is another common issue. You might notice your fish losing their balance or breathing heavily. Again, to treat, change the water and wipe down all the sides of the aquarium. Adding salt will help eliminate some of the stress your fish is experiencing, too.
A bacterial infection in your discus fish must be treated by cleaning the tank and adding an antibacterial agent, which can be purchased at your local pet store. Your fish will have protruding eyes as well as redness.
Fin rot and skin ulcers, common in many species of aquarium fish, are also caused by poor water quality. You might notice the disappearance of your fish’s fins as well as lesions and loss of appetite. These can both lead to death, so it’s important to take care of these diseases right away.
Tips on keeping discus fish in good health
Discus fish are extremely shy, and need time to recover after being moved to a new tank. Try to avoid turning on the light or standing near the tank. Give them room to hide while they get used to their new surroundings. Chemical test the water and make sure it is of the utmost quality before introducing your fish.
You should also consider adding a deworming medication while you are in the process of acclimating your discus. This will help ensure that your fish remain free of parasites and stay healthy.
Breeding Discus Fish
It can be difficult to tell the difference between male and female discus fish. You can often only tell the difference during the spawning period. If you have more experience in identifying the different sexes, look at the head for clues. Male fish will have a receding forehead and fuller lips.
If you plan to breed your discus fish, consider purchasing more individuals. You need at least six to eight young species to ensure that there is a couple among them. Discus fish will couple off on their own, but you need to provide a large tank for them in advance. Juvenile fish turn into adults very quickly, so a separate spawning tank is not a bad idea, either.
Discus fish care for their young, producing a secretion through their skin which the larvae live off during their first four weeks of life. Parent discus fish stay with their young for several weeks, allowing them to feed before gradually “weaning” them off. This is a rare behavior in fish, but common in other cichlid species as well. Discus fish reach sexual maturity in about a year.
A common challenge in breeding discus fish is that the couple will occasionally eat its own eggs. This is common among young fish. Consider using a glass wall or netting to separate young discus fish from parents or other discus who might eat the eggs.
Discus fish are incredibly susceptible to nitrate and ammonia levels, as well as water quality issues in general, a unique challenge in raising them that you likely will not have as intensely with other fish species. They will change color and breathe heavily if there is too much ammonia or even low levels of nitrite. If you have high levels of nitrate, you can lower them by adding aquatic plants and removing decayed mater.
Change your aquarium water by at least fifty percent every week to reduce nitrates and to replenish minerals. Because discus are messy feeders, they will make a huge mess in the aquarium and contaminate the water if you aren’t careful about cleaning the tank.
Another interesting fact about discus fish is that they are one of the few species that have populations that are increasing instead of decreasing over the years. Overfishing and destructive fishing methods led to diminished populations of brown discus, but other varieties, such as blue and red discus, are actually thriving.
Are Discus Fish Right For You?
The discus fish is an incredibly beautiful fish that offers vibrant coloring and a stately appearance to your tank . Although these fish can be somewhat more demanding than other aquarium species, they are a fantastic choice if you are looking to add some life and color to your otherwise boring tank.