Discus Fish: Complete Care Guide (Diet, Tank & More)

Discus fish are a great addition to freshwater tanks because of their peaceful nature and beautiful colorations. 

However, they can be a bit larger than most other freshwater fish so it is important to have the space needed for them.

Read on to learn everything you need to know about keeping discus fish and how you can ensure they are thriving in their environment. 

Discus Fish Care Guide

Discus fish are a category of freshwater fish that come in a variety of colors. For the most part, they are peaceful fish that love to be in a community amongst themselves or just of their own kind. They can range between 4.6 to 8 inches so they need a large enough tank to accommodate this.

Appearance and Temperament

Appearance

Discus fish have four main colors as well as a variety of patterns and markings. Discus fish that are in captivity are typically brighter than those in the wild. 

This is because of hybridization from captivity breeding. Their full color emerges as they mature and will change color according to their environment.

Typically heckle discus are pale yellow and have three vertical stripes of that color. One of those stripes runs through their eye. 

Blue and green discus have red dots instead of vertical stripes. A brown discus has nine vertical stripes over their bodies.

Discus fish have flat rounded bodies that are similar to an angelfish without fins. There are also different variations of colors and patterns due to breeding that can be found.

Lifespan and Size

In captivity the discus fish can grow up to 9 inches long! In the wild, they will typically only grow to 4.8 to 6 inches in length. 

The male discus is slightly larger than the female discus. 

Also in captivity, they can live for an average of 10 to 15 years. In the wild their lifespans are much shorter due to predators.

Temperament and Behavior

Discus fish are very peaceful, often shy, fish that are intimidated by aggressive, larger, and faster fish. 

This is because they thrive when they are able to move slowly in their group around the tank. Discus fish are active during the day and will sleep at night.

They are part of the cichlid family and because of this, they can be territorial. Due to this, they should be kept with fish that are similar in size as well as similar speeds.

Diet and Feeding

Discus fish are omnivores and in the wild, they will eat insects, plankton, and invertebrates. 

As with any other species, it is best to mimic this diet in captivity. It is important to have a well-balanced diet for them to thrive. 

Also, the variety in food will provide a variety of options as they can be picky eats.

A high-quality flake or pellet is a great foundation for their diet. They will also need to be fed live or frozen foods as a source of protein. 

Live food such as bloodworms, brine shrimp, blackworms, and microworms are great options. 

Some foods such as shrimp eggs are considered pigment-enhancing foods and will help the discus develop more vibrant colors.

Because of the flat shape of their bodies, they eat smaller meals throughout the day. 

Also, discus fish have quite small mouths and can sometimes have difficulty eating some foods if they are too large. 

It is very important to not overfeed your discus. To avoid this there is a general rule when feeding discus fish. 

This rule states to feed them approximately 3% of their body weight each feeding. It is recommended to feed adult discus fish, one year and older, 2 or 3 times per day.

Ideal Discus Tank Mates

As previously stated, discus are peaceful but intimidated by poor tank mates. 

Keep in mind they are schooling fish and need to be kept in groups of their own kind of at least 6. If you plan to add tank mates, ensure you have a large enough tank. 

Discus prefer a few tank mates outside their group rather than large groups of other species.

Discus are peaceful and make great tank mates. They do well with other peaceful tank mates. 

Tank mates for discus should be slow-moving, non-aggressive, and require similar tank conditions. 

Tank mates should also be large enough to not be a meal for the discus, best to avoid nano fish.

Examples of ideal tank mates for discus fish:

• Cardinal Tetras
• Cory Catfish
• Bristlenose Pleco
• Hatchetfish
• Clown Loaches

It is best to avoid faster fish that will create competition for food. As discus are slower moving and will take longer to reach the food. 

This can cause them to not get enough food which will result in a lack of nutrients. Also discus fish are slow eaters

Tank mates that are aggressive, fast-moving, and larger should be avoided as they will stress the discus. Examples of tank mates to avoid are:

• Angelfish
• African Cichlid
• Oscars
• Barbs
• German Blue Rams
• Zebra Danios

Aquarium Setup & Water Conditions

Discus grow quite large and because of that they need a bigger space. It is a general rule that there should be 10 gallons for every discus fish. 

They are schooling fish and need to be in groups of their own kind. A group of 5 can live comfortably in a 55-gallon tank.

Discus fish are harder to keep as they have a very specific diet and tank needs. Because of this, they are considered a specialty breed. 

In captivity they prefer stable environments, the tank conditions will have to be maintained and stable. 

Ideal water conditions:

• Water Temperature: 82 to 88
• pH Level: 6 to 7
• Water Hardness: 2-8 dGH

Discus fish prefer higher water temperatures than a lot of fish. This is because they are bred and raised in these higher temperatures.

The higher heat helps their metabolism run well, they can grow faster, they are more active, and their colors are shown more. 

Forcing them to temperatures lower causes discomfort as well as making them more prone to diseases. 

Because of these higher temperatures, you will want to add air stones or a bubbler. As the higher temperature will decrease the oxygen levels in the water.

Discus are larger fish, and if you have 5 in a 55-gallon tank you will want a better filtration system. 

As they are larger and will create more waste, without extra water outside the 55 gallons, the tank will become dirty rather quickly. 

Consistent and frequent water changes will need to be done in order to keep the tank clean.

Keep Discus in a Planted Tank?

Keeping discus in a planted tank has many benefits. Plants are great for adding some much-needed oxygen back into the tank water. 

With the higher heat lowering the oxygen plants are a great way to ensure your discus has enough oxygen. However, you will need to choose plants that can withstand high temperatures.

Another benefit of a planted tank is that the plants will serve as another filtration system. As previously stated they are larger fish that produce more waste, and your tank will become dirty more quickly. 

Plants absorb ammonia and nitrates from the water as they grow. This will keep the water chemically cleaner for the proper water parameters and quality.

Some plant options such as plant substrate as UNS Controsoil can help water parameters remain constant. 

It buffers and stabilizes pH to an optimal level that is more suitable for tropical fish. Planted tanks with a nutrient-rich substrate are ideal for Discus fish.

Having a planted tank for discus will help maintain the water quality they need. 

Even hardscapes such as driftwood are also great additions as they also lower water hardness and pH.

Breeding Discus Fish

Breeding discus fish can be more challenging, as there are no distinct ways to determine the sex of the discus fish. 

Also, they take longer to reach sexual maturity, which will take two to three years. 

To determine a mating pair you will have to observe your discus fish as they will pair off naturally. 

When two discus fish start to exhibit territorial behavior, transfer them to a separate breeding tank as this is your mated pair.

The breeding tank should have the same water conditions and temperature as their home tank. 

It should be at least 20 gallons but no more than 30 gallons. Also, they should be fed an optimal diet to trigger spawning, a diet full of higher protein foods such as live foods only.

The breeding tank should not have a substrate to keep the tank cleaner. Three should be driftwood placed around the tank as well as flat rocks. 

These will serve as egg-laying surfaces for the discus fish. 

You can also place a breeding cone inside the tank to provide a hard surface for the eggs as well as encourage them to lay eggs.

The female’s gestation will be less than four days. You will need to keep the parent fish in the tank as the eggs will be laid on. 

This incubation period will last about ten days. When their eggs hatch they will live off of the mucus on their parent’s scales. 

This provides them with plenty of nourishment and should be left to eat this as long as they can as this helps prevent disease in the fry.

Removing the parent fish should happen after about three or four weeks. This is when the parents are going to become done with being fed off of. 

Also at this point, the fry are about the size of a thumbnail and starts causing the parent fish to become hurt.

At this point, it is best to start treating the water for the fry to protect them from diseases such as gill flukes. 

Treating the water is very important in the survival of the fry discus. If the water is not treated the fry will start dying until there is none left. 

This is also referred to as four-week syndrome and occurs after the fry stops feeding off the parent’s mucus.

After the fry are separated from the adults at four weeks they should be fed a high-protein diet. 

Great options for this diet are baby brine shrimp and blended proteins such as a beef heart. Once they are large enough they can be fed the same diet as the adult discus. 

Origin and Distribution

The discus fish originates from South America, in the Amazon river. The color of the discus fish will tell you which basin of the Amazon River it is native to. 

The blue discus is native to the eastern Amazon. The green discus is native to the western basin, and the red discus is native to the Rio Negro area.

Discus fish are also a specialty breed and are oftentimes not available in local stores. Because of this, they are not always in the best shape. 

It is best to purchase discus fish from a specialty breeder to ensure health of the discus fish.