Discus Fish

Discus Fish 101: The Ultimate Care Guide

Over 2 centuries ago, discus fish resided only in the Amazon River. However, due to their popularity among fish enthusiasts, these guys are now found all over the world.

Although they can be a little bit pricey, discus fish are definitely worth the investment. Not only are they absolutely beautiful creatures, but they’re also relatively low-maintenance (compared to other fish, at least).

In this guide, I’m going to cover everything you need to know about caring for discus fish. From feeding and tank requirements to breeding and common health problems, I’ve got you covered!

Discus Fish Tank Requirements

Water Parameters

Water Cycling

I know. You’re probably thinking, “Ugh, do I really have to cycle my tank?” The answer is yes – and it’s not as difficult as you might think.

Basically, the process of cycling a tank involves establishing beneficial bacteria colonies that will help to break down waste products in the water. This is important because waste can be toxic to fish if it builds up too much.

To cycle a tank, you’ll need to add a source of ammonia – this can be something as simple as pure ammonia from the hardware store or waste from another fish tank. Once you’ve added the ammonia, you’ll need to test the water regularly to see how the levels are changing.

When the levels of ammonia and nitrites start to drop, that means the bacteria colonies are starting to form and your tank is being cycled.

If you don’t want to cycle your tank yourself, you can always buy a fishless cycling kit from your local pet store. This will provide you with everything you need to get the process started.

When it comes to water changes, you should perform 25% to 50% once every week depending on the size of your tank and the number of fish you have.

To make sure your water is properly balanced, you’ll need to test it regularly. I recommend using API Freshwater Master Test Kit for its accuracy and ease of use.

Water Temperature

If you are used to a specific temperature in your house, you might be thinking that your discus fish will like it too. Unfortunately, that’s not the case!

Discus fish come from the Amazon River Basin, which has a water temperature of around 82°F to 86°F. This is much hotter than the average house temperature, so you’ll need to take some steps to raise the temperature of your tank water.

One way to do this is to use an aquarium heater. I recommend the Hydor Theo 50 Watt Aquarium Heater. Another way to raise the temperature of your tank water is to use a heat lamp. This is a cheaper option, but it’s not as effective or efficient as using an aquarium heater.

To ensure you’re on track, I recommend using an aquarium thermometer or you can just invest in an aquarium heater with a built-in thermometer.

pH Level & Water Hardness

In my experience, the pH level and water hardness are the most essential water parameters to monitor while maintaining discus fish. Any minor variations in these values might lead to severe problems that you don’t want to deal with!

When it comes to the pH level, discus fish prefer water that is slightly acidic with a pH of 6.0 to 7.0. If your water is too alkaline or too acidic, you can use a water conditioner to adjust the pH level. I recommend using Seachem Prime because it’s safe for both fish and plants.

As for water hardness, discus fish prefer soft water with a hardness of 1 to 4 dH. If your water is too hard, you can use a water softener to adjust the hardness.

Tank Setup

Tank size

When it comes to tank size, most people want the simplest and cheapest method to begin with. They want to know the minimum discus fish tank size rather than what is the best for their pet fish.

However, I can’t blame them! After all, we’ve all been there before. We get excited about a new pet and want to take them home as soon as possible without doing any research first.

Unfortunately, this is often not the best decision for the pet. In the case of discus fish, they are schooling fish, which means they feel at home when they are in a group.

Aside from that, a big tank will save the trouble and money of having to upgrade in the future. It’s better to do it right the first time rather than have to go through the hassle of moving your fish and all their belongings to a new tank later on.

So, what is the minimum discus fish tank size that you should start with? I recommend a tank that is at least 55 gallons for six young discus fish.

As they grow older and larger, you will need to increase the size of your tank to 75 gallons. However, if you have the space and budget for a bigger tank, go for it!

In case you are starting with a single discus fish, you should still get a tank that is at least 10 gallons in size. This will give your fish enough space to swim around and be comfortable without feeling cramped.

Further, your tank should be tall rather than wide. This is because discus fish grow to be around 6 to 8 inches in height. A tall tank will give them plenty of vertical space to swim up and down.

Aquarium Filter

These fish come from slow-moving waters in the Amazon, so they are not used to the hard flow in their tanks. In fact, too much water movement can stress them out!

Also, they can fill up a tank quickly with their waste, so you need an aquarium filter that can handle the bio-load.

So the level of filtration should be twice the size of your tank. For example, a 50-gallon tank should have a canister filter that is at least 100 gallons per hour (GPH).


These big eyes pals need dim lighting to feel comfortable. They are used to living in the shade of the Amazon rainforest, so bright light is not something they are used to.

To replicate their natural habitat, you should make sure they get 10 to 12 hours of sunshine each day. You can do this by using an aquarium hood with fluorescent bulbs that emit low levels of light.

Tank Decorations


Among the tree roots and limbs in their natural habitat, discus fish love to hide and lounge around. To give your fish the same feeling of security in their tank, you should add some driftwood.

Not only will this provide them with a place to hide, but it will also help to create a more natural look in your tank. However, be cautious when choosing driftwood since it might alter the pH level of your water.

For example, you can use Manzanita driftwood, which is safe for both fish and plants. Also, it blends well with most aquariums and doesn’t change the water parameters.


The substrate is the material you use to line the bottom of your tank to give it a natural look. Not only it is aesthetically pleasing, but it also provides nutrients for your aquatic plants.

If you’re starting your planted aquarium from scratch, I recommend using inert gravel as a substrate. This is because you have to fertilize more frequently to keep demanding plants alive and healthy.

Also, make sure that the gravel is fine-grained to avoid harming your fish. They can easily get caught in between the gaps of bigger gravel and injure themselves.


Aquatic plants are essential in creating a natural environment for your discus fish. Not only do they make your tank look more beautiful, but they also provide your fish with hiding places and oxygenate the water.

Further, they can maintain the temperature of your tank and help to keep the water clean. Some of the best plants for a discus fish tank include:

Discus Fish Tank Mates

It’s easy to keep discus fish with the same species but do you really think it is the same as with other fish species? These fish are very shy and not used to other tank mates. So, it’s best to keep them with their own kind.

However, if you want to add other fish to your tank, there are some aspects you need to take into consideration. These are the most important ones:

Water Temperature

Imagine that you’re from the Amazon rainforest and suddenly you’re transferred to a cold water tank. You would be pretty stressed out, right?

Well, that’s how your discus fish feel when you add them to a tank with a different water temperature than what they’re used to. So, when you decide on tank mates for your discus fish, make sure they can tolerate the same water temperature.

Water Parameters

These picky fish only thrive in soft acidic water with a pH level of 6.0 to 7.0. So, their tank mates should be able to withstand these water conditions as well.

Otherwise, your tank will quickly become a disaster, and your fish will start falling apart like a house of cards!


As I mentioned before, discus fish are pretty shy. So, their tank mates should have a peaceful temperament to make them feel comfortable in their new environment.

Also, their peaceful nature might make them an easy target for aggressive fish. So, make sure to choose tank mates that won’t bully or harass them.

Tank size

Most of the aggression results from the lack of space. While most people keep their minds up about the discus large tanks, they forget that their tank mates need the same amount of space.

If the other fish is much bigger than the discus, it will quickly outgrow the tank and make the discus feel like they’re in a prison cell. So, choose wisely!

Unless you can invest in a much bigger tank, I recommend sticking to the same species. This way, you can avoid any potential problems and create a happy environment for your fish.


A biotope is a naturally occurring environment that includes all the elements that a particular species need to survive.

Just like you when you go to someplace new and you want to make some new friends. Would you feel more comfortable in a group of people that have the same interests as you or in a group of people that have completely different interests?

Surely you would feel more comfortable with people that share the same interests as you. Thus, you should choose tankmates that will also like having gravel, plants, and other decor items.

If you’re having trouble finding fish that fit your needs, try looking into peaceful bottom-dwellers or algal eaters.

Discus Fish Diet

Discus fish are omnivores, which means they eat both plants and animals. In the wild, they mainly feed on small insects, crustaceans, and worms.

To ensure that your discus fish are getting the nutrients they need, give them a diet that contains 35-45% protein. This will help them to grow and develop at a more natural rate. Newly hatched fry and juvenile discus require a higher level of protein in their diet, up to 50%, in order to grow more quickly.

Also, it’s worth noting that the discus diet isn’t entirely protein-based, and they require additional fats and nutrients. And, like all living things, they require specific vitamins in order to satisfy their nutritional needs.

Since vitamins are responsible for several key bodily functions, including the immune system and reproductive system, it is important to make sure your fish get the right amount. For this purpose, you should offer them a mix of live, frozen, and prepared foods.

Here are some of the best foods for discus fish:

  • Bloodworms: These are the larvae of midge flies and are an excellent source of protein for your discus fish. In addition, they are a good source of essential amino acids, which are important for the health of your fish’s skin and fins
  • Brine Shrimp: Brine shrimp are a type of crustacean that is high in protein and fat. Also, they are rich in saturated and unsaturated fatty acids that improve the total health of your fish
  • Tubifex Worms: Although tubifex worms don’t have as many essential amino acids as bloodworms, they make up for it in protein. Also, their larger size satisfies bigger discus fish
  • White Worms: Not only are white worms a superb source of protein and fatty acids, but they’re also packed with Vitamins B1, B2, and G. Therefore, they’ll make an excellent energy boost for your fish!
  • Beef heart: It’s a wonderful source of fat and protein, making it excellent fish food. However, the excessive amount of it can induce digestive issues as well as other diseases unless you give them carefully controlled doses

Discus Fish Breeding

Breeding discus is like running a marathon. It’s not for the faint of heart. To go through with it, you’ll need nerves of steel, patience, and a bit of luck.

Some factors that you must consider before breeding discus fish:

Selecting a Breeding Pair

I believe that this is the most important factor when it comes to breeding discus fish. The pair must be compatible with each other in order to produce healthy offspring.

Another thing to take into account is the age of your discus fish. It’s best to choose a younger pair that is around 12 months old. This is because they will be more resilient and have a higher survival chance during the breeding process.

Further, you should make sure that you have a boy and a girl. The easiest way to tell the difference is by looking at their breeding tube. The male’s breeding tube will be longer and thinner than the female’s.

Instead, you can just put six juveniles in a tank and wait for them to pair off.

Prepare a Breeding Tank

If it’s your first time breeding discus fish, you might think that any old tank will do. However, this couldn’t be further from the truth.

You need to prepare a special breeding tank that meets the specific needs of your discus fish. For example, the water temperature should be around 86 degrees Fahrenheit. Also, the pH level should be between 6 and 7 and the hardness should be around 1-4 dGH.

In addition, the water should be well-filtered and the tank should have plenty of hiding places. This is because discus fish are shy by nature and need to feel secure in order to breed.

Finally, you’ll need to add some live plants to the tank. These will provide your discus fish with oxygen as well as a place to lay their eggs.

Provide Your Fish with a Well-Balanced Diet

Conditioning your discus fish is crucial to induce their breeding behavior. For this reason, you need to provide them with a well-balanced diet that is high in protein.

To ensure your fish are healthy and well-fed, you can include mosquito larvae, adult brine shrimp, and white worms in their diet.

In addition to these live foods, you can mix in powdered spinach, spirulina, or high-quality flake food for a complete and balanced meal.

Watch for Mated Pairs

Once you’ve conditioned your discus fish and they’re ready to breed, you’ll need to keep a close eye on them. This is because the male will chase the female around the tank until she agrees to mate with him.

When you see a mated pair, you’ll need to quickly remove them from the main tank and put them in their own breeding tank.

After that, the female will lay her eggs on a leaf or the glass of the tank. Once she’s done, the male will fertilize them.

Decide Whether to Raise the Young Discus Alone or with the Parents

Discus fish are wonderful parents who will do an excellent job of raising their young. This might be useful if you want to breed them for many generations.

This is because raising baby discus fish alongside their parents will improve their chances of survival. Also, it will reduce the amount of stress that they experience.

However, sometimes it’s best to raise the young discus fish alone. This is because their parents might eat them if they’re not well-fed or they are breeding for the first time.

In both cases, you should offer the right food and provide plenty of hiding places. Plus, you’ll need to do regular water changes to keep the tank clean.

Last Words

Discus fish are some of the most beautiful and popular aquarium fish. They make a great addition to any tank and their unique personalities will keep you entertained for hours.

If you’re thinking about breeding discus fish, I hope this article has helped you get started. Just remember to be patient and take your time. With a little bit of luck, you’ll be successfully breeding discus fish in no time!

Do you have any tips for breeding discus fish? If so, please share them in the comments below!