Discus Fish (Symphysodon): Ultimate Care Guide


Scientific NameSymphysodon
Common Name(s)Discus
OriginSouth America, Amazon River Basin
Temperature Range82–88°F (28–31°C)
Water pH6.0-7.0
Adult Size6-9 inches
DietCarnivorous, live fish food, frozen food

Discus Fish Facts

  • The discus fish is a type of cichlid and comes in a variety of beautiful, rich colors.
  • Fry start out their lives by being carefully cared for by both parents, and even feed on a secretion from their parents.
  • Valued for their beauty as much as for their willingness to interact with their owners. They can even be fed by hand.

One of the most beautiful and popular aquarium fish is the freshwater fish known as the discus fish, or Symphysodon aequifasciatus (blue discus or brown discus), S. discus (red discus or heckle discus), and S. tarzoo (green discus), depending on the color.  Discus fish go by other common names such as pompadour fish and king of the aquarium.  Discovered in 1840, the discus fish have a numerous amounts of subspecies under their belt.  They come from the Amazon river basin in South America.  The blue discus tends to be native to the eastern Amazon basin, while the green discus is native to the western Amazon basin, and the red discus is native to the Rio Negro area.  Discus fish prefer to live in floodplains with other living organisms and plants.  Therefore, discus fish really love clean, filtered water with a somewhat busy tank life. 

Discus Fish
Discus Fish

Discus fish have a very unique appearance as they have an ionic round shape to their bodies with long fins sticking out both above and below the body.  Discus fish are members of the cichlidae family and they come in many different colors, ranging from solid colors to differentiating patterns of beauty.  With four primary jewel-like colors, discus fish are known to have different markings and patterns, which have become very popular amongst hobbyists.  Most of the discus fish with bright marks result from hybridization of the fish and cannot be found in the wild.  Even though discus fish have flat sides to their round bodies, do not confuse them with angelfish.  The discus fish’s fins do not extend as far as the angelfish. 

Discus fish are known for how difficult they are to keep because of the precise aquarium needs.  In order to ensure the happiness of your discus fish, especially if you have them in a large group, then you will need to follow this guide in caring for your discus fish. 

Discus Fish Care

Discus fish are a bit more complicated to care for than other typical aquarium freshwater fish.  Discus have very specific requirements that can make them quite a challenge to keep in your tank.  It is recommended that you keep discus fish in a group, as pairing them with other tank mates can be difficult.  By having a bunch of discus fish together, it makes caring for them easier too.  Discus fish tend to be peace-loving fish that slowly swim around the tank.  If they are ever intimidated by other larger fish, then the discus fish will usually hide in a plant or cave.  They are active in the day and sleep at night.  Discus fish can be territorial based on the tank size, so it is best to put them with other fish that are slow swimmers and don’t compete for food.  A group of six should be good for beginners. 

Temperature and pH

One of the major reasons why discus fish are so complicated to take care of is because of the water requirements.  It has been suggested that discus fish need their water changed on a daily basis.  While water does need to be changed often for the discus fish, this mainly depends on the size of your tank, how many fish you have, and how much waste has built up inside the tank.  How much you feed your fish will also have an effect on how much you need to change the water.  There is no broad stroke answer because everyone’s tank setup is different.  Some suggest daily changes while others say changing 10%-25% of the tank’s water weekly should be enough for the discus fish.  Ideally, you will want to keep the nitrate level lower than 40 ppm for any planted tank and lower than 20 ppm for non-planted plants.  The discus fish like clean, filtered water so be ready to make water changes. 

Yes, the discus fish like warmer water.  The temperature for the discus fish needs to be set between 82–88°F (28–31°C).  You should have soft freshwater in the tank with a pH level between 6.0–7.0 pH.  Most discus fish that are bought from an online store can be added directly to a tank that is ready.

Discus Fish Size

If you take good care of the water requirements for the discus fish, they can grow up to six to nine inches long.  They also grow in height as well as their round dish shape.  Since they are territorial, they need a proper space to thrive in that looks as natural as possible.  But the size of the discus fish will greatly be determined by how well you keep the water.  As mentioned before, it is important to keep an eye on the water and change it fairly regularly.  A happy discus fish will thrive in clean filtered water.

Food and Diet

When it comes to feeding the discus fish, one thing of importance is the size of the discus fish’s mouth.  It is quite small and so any food that you get cannot be too large of chunks.  If you happen to see the discus fish eating food and then spitting it back out, you may want to get something different for them to munch on.  Something like frozen bloodworms are great because of their skinny shape, which make it easy for the discus fish to gobble it up.  Other types of food that can be recommended is Hikari Vibra Bites, Sera Discus Granules, Tetra Discus Granules, and Hikari Discus Bio-Gold.  You can also feed them brine shrimp, blackworms, and live microworms.  You can also mix the blackworms with a vitamin boost to give them the nutritional supplements that the discus fish needs to thrive.  Discus fish are required to eat several times a day and they are slow eaters.  If they are young discus fish, then you should be feeding them about ten times a day.  Juvenile discus need five feedings per day and adults only need twice a day. 

Discus Fish in Aquarium
Discus Fish in Aquarium

Lifespan

One major factor of the discus fish’s lifespan, as well as any other fish you keep, is the way your tank is cared for.  Discus fish can generally live on average about ten years, however, there have been records of discus fish living to fifteen years.  If you are a person that moves around a lot, it might be better to hold off on the discus fish, since they require so much specific care. 

Tank Size and Setup

For any beginner of fish keeping, it is always a good move to consider what kind of fish work well together, how many fish you plan to have in your tank, and the types of fish that you want to keep.  For the discus fish, a bare bottom is a good choice to start.  Bare bottom tanks are easier to control water parameters and diseases, and they are much easier to clean.  These are major factors when keeping discus fish healthy. 

Furthermore, discus fish prefer larger and deeper tanks, so it is recommended that your tank be around sixty gallons and that are around sixty centimeters in height.  When having a lot of fish in one tank, it really helps their stress levels out when you give them plenty of room to swim in.   Since discus fish are territorial, the tank size will help them out a lot if you can make it bigger.  If you are planning on having a whole group of discus fish or anything other fish friends, then it is recommended that you go above a sixty-gallon tank.  You can put some plants, driftwood pieces, and some caves into the tank, but it is best not to overcrowd the tank.  The more stuff that you put into the tank, the less room there is to swim inside the tank. 

In the wild, discus fish are used to slow-moving rivers and lakes in the Amazon basin.  They tend to congregate close to fallen trees and branches near the river banks.  Therefore, in captivity, discus fish prefer stable environments.

One thing to keep in mind is that when you add a newly bough discus fish from a store, do not be alarmed if you see them lying on its side at first.  This does not mean that the fish is ill or dying.  It just simply means that the fish is getting used to the change in water pressure and is a completely normal reaction when introduced to a new setting.  It should go away fairly quickly once they get acclimated to their new environment. 

Breeding

Breeding discus fish is a complicated and difficult task.  The breeding process for discus fish is very much like that of angelfish.  The first step in breeding discus fish is to get a pair. There are a couple of different ways this can be done.  You can buy a bonded pair online, however, this can cost in the upwards of $500.  The other option is to buy 6-8 baby discus fish and wait about a year for them to pair. 

There are a few signs to look out for to tell when two discus fish have paired off.  If you see a male discus fish guarding a specific area in the tank, he is probably trying to interact with the females.  He will use that spot as his own and will either pursue a female or wait for one to approach.  The male and female will often bow their fins to each other, which is like a bend.  Once they have reached this point in the breeding process, many breeders will move those discus fish into their own separate tank. 

When the discus fish are ready to spawn, they will clean off a particular space in the tank.  As an important side note, make sure to keep the lighting schedule consistent as it affects the discus fish spawn time.  After the area is cleaned, the discus female will lay her eggs.  After about three days or so, the eggs will hatch and the fry will be moved around for several days.  The fry will soon become free swimmers and eat the mucus coat off their parents’ skin.  It is important to keep the parents close by their newly hatched young for this reason. 

After about three or four weeks after hatching, it is best to then separate the parents from the fry because the parents will start getting fed up by the larger, hungrier babies eating their mucus constantly.  Now, you can feed the fry separately with a high protein diet.  It is also time to start treating the tank lightly for gill flukes and other diseases as the fry are very susceptible during this time.

Trying to determine which discus fish are males and which ones are females?  Male discus fish tend to be a bit larger than females.  Otherwise, there is not a lot to decipher males and females.

Diseases

When caring for your discus fish, it should go without saying that the better that you change the water, clean the tank, and feed the discus fish, the healthier your fish will stay.  Assuming that you are doing all of these things, you should know that discus fish are more susceptible to common warm-water bacterial infections such as hole-in-the-head and cotton wool.  As mentioned before, the discus fish are also prone to internal and external parasite infections such as gill flukes. 

There are other common fungal infections which can attach themselves onto the discuss fish and start growing.  You’ll first notice a cotton-like appearance on the surface of the discus’s skin.  You might also see the discus fish “rubbing” itself against objects in the tank in order to itch the infection.  You may also notice the fins being clamped or they drastically change their eating habits. 

If you do not keep the discus fish’s high water temperature requirements up to par, then the may be affected by common cool-water parasites and illnesses like ich, which is a white spotted disease.  As soon as you notice any signs of illness with your discus fish, be sure to quickly identify the problem and treat it, otherwise your discus fish will not survive. 

Tank Mates for Discus Fish

Discus fish are not entirely aggressive, but they are territorial.  Therefore, the best tank mates for them are slow-moving and non-aggressive.  It might be better to have fish that are larger than the discus fish so that the discus fish does not accidently mistaken it for food.  Furthermore, you’ll need to have tank mates that also share the same water requirements.  This is why it was mentioned before about planning what kind of tank you want to have. It is not as simple as just throwing a bunch of fish together into a tank and calling it a day. 

One of the best tank mates for the discus fish would be the corydoras.  Discus fish tend to swim in the middle-upper region of the aquarium, while corydoras tend to stay more at the bottom region of the tank.  This allows for a great balance in the tank.  Keep in mind that only certain corydoras, like sterba’s corydoras, enjoy the warmer water temperature so be sure to do your research before buying one. 

Other great tank mates for the discus fish would be many from the tetra family, such as cardinal tetras, neon tetras, and glowlight tetras.  You can also combine the discus fish with hatchet, piecostomus catfish, and clown loaches.  All of these fish should be good tank mates for your discus fish.

However, you should avoid fish like goldfish, angelfish, African cichlid, and Oscar fish.  These fish are not good tank mates for the discus fish and will cause many problems for your tank’s environment.

Types of Discus

There are mainly four primary colors for discus fish, even though they all have unique displays of markings and patterns.  One of the draws of this fish is its beautiful colors and design.  For example, heckle discus are typically pale yellow and usually have three distinct vertical stripes.  However, there are other types of discus fish that are a bit more popular with fish enthusiasts. 

Blue Discus

The blue discus fish, Symphysodon aequifasciatus, is obviously popular because of its vibrant iridescent blue color.  This is a result of the discus being caught in the wild and using selective breeding to get the favorable mutations of the color.  They are unique because of their thin, oval shaped bodies and long decorated fins.  Also known as blue diamond discus, they are just as picky as regular discus with their water requirements.  They can reach a maximum size of 8.5 inches and need their water changed on a regular basis to ensure their health.  In the wild, the blue diamond discus stretch from the Amazon to the Rio Negro regions in South America.  It should be noted that this is not a fish for beginner hobbyists as it takes very special care to ensure its health.

Red Discus

The red discus, Symphysodon discus, is a subspecies of the discus fish that comes from the same area as the other discus fish.  It is named the red turquoise discus because of its fiery red design.  This is a favorite with hobbyists as well, but also requires a high level of care and maintenance.  The red turquoise discus has red eyes, red skin, and has a brilliant red colorization on the fins.  They are not territorial as other discus fish unless they are breeding.  Otherwise, they are calm and peaceful fish that will add bright and beautiful colors to any aquarium.

Green Discus

Green discus fish, Symphysodon tarzoo, are also known as red spotted fish because they can change their color based on age, mood, water quality, or region.  In the wild, green discus live in the deeper parts of water.  The green discus fish have a flattened and rounded shape.  One thing that sets it apart from other discus is the fact that its fins extend down to its tail.  It has gorgeous asymmetrical and metallic stripes running parallel along the belly.  Generally speaking, the green discus is a bit smaller than other discus as it tends to average out at around six inches. 

Where to Find Discus Fish for Sale

If you are looking to buy a discus fish or a group of them for your tank, there are a few things you should be aware of.  Discus fish tend to be on the more expensive side because of the complicated nature of care.  It takes discus fish longer to reach maturity unlike many other fish.  Therefore, if you are buying a discus fish, be sure to know what you are getting into.  Don’t buy the cheaper discus as they are probably at that cost because of the care (or lack thereof) of the shop selling them. 

Fish Laboratory

With decades of collective fishkeeping experience, we are happy to share the fish care tips that we've picked up along the way. Our goal at Fish Laboratory is to keep publishing accurate content to help fishkeepers keep their fish and aquarium healthy.

Recent Posts