Discus Fish Tank Requirements

Setting up a discus fish tank can be a daunting task, but it’s also an immensely rewarding one.

Discus fish require a special type of aquarium setup and specific water conditions, so aquarists who are interested in keeping these beautiful creatures should be sure they are aware of the necessary discus tank requirements.

In this blog post, we will discuss the key things you need to know before setting up a discus fish tank.

So if you’re thinking about adding some discus fish to your aquarium and are confused about how to care for them, you are just in the right place.

1. Water Parameters

a. Water Change

When it comes to water cycling, there is really no standard process to do it.

The frequency of water changes in your discus tank will be determined by a variety of criteria including:

  • How many fish are there in your aquarium? 
  • What’s the size of the tank? 
  • Are they juvenile fish or adult specimens? 
  • Is filtration effective? 
  • How often do you feed your fish?

All of this information can have a big influence on how frequently you need to change your aquarium water.

For example, if you’re raising a group of juveniles, you must make water changes on a daily basis or every other day.

Anything less will result in your fish’s growth being stunted since poor water quality is the main thing that harms discus’ growth.

Also, you should keep in mind the quantity of food you’re feeding your fish.

More food equals more waste, nitrates, and ammonia which means feedings on a regular basis go hand-in-hand with water changes on a regular basis.

Now, you might be wondering: How much percentage of water do I need to change? 

As we mentioned, there is no specific answer for this question, some people do 100 percent water changes every week while others don’t, thus It’s up to you to figure out what’s best for you.

However, from our experience, 50 percent a week water change is more than enough, especially if you are a beginner and don’t have the time for more frequent changes.

Changing your discus’s water is extremely important, as it eliminates dangerous pollutants and other impurities, so If you can’t modify it on a regular basis, make sure to do so at least 25% change once a week.

What’s The Best Time For A Water Change? 

Discus are nervous fish, and they can easily become anxious especially during water change time.

Therefore, setting up a water change routine is very crucial to reduce stress for your discus.

This will make your discus accustomed to the idea of a water change and make them ready for it when the time comes.

Do Discus Really Need Daily Water Changes?

Discus fish don’t require daily water changes unless they are juvenile.

However, they still require regular water changes, and if you want to cultivate a robust fish that is healthy and large, you must do so.

b. Discus pH Level & Water Hardness

Other environmental conditions to consider are pH and water hardness.

In our experience, both wild-caught and captive-bred discus do well when the pH levels are between 6.0 and 7.0.

The same thing can be said about water hardness; discus is usually tolerant of soft to medium hardness 1° to 4° dKH (18 to 70 ppm).

Can Discus Live In Higher pH?

Despite the fact that the optimum range for pH is 6.0 to 7.0, discus can live in a more acidic environment.

Generally, higher pH levels are less harmful than lower ones because they are less acidic.

c. Water Temperature

Discus fish come from Brazil where the waters are always warm, therefore, they need high temperatures in order to grow and remain healthy.

If you try to force them to cool down, they are going to be stressed out and this could lead to death.

On the other hand, when the heat is kept high, your discus becomes more active, their metabolism functions properly, they develop faster, and their colors become more intense.

If you want to properly care for discus, keep the water temperature around 85 to 86°F, which may differ from your normal fishkeeping practices, so you might need a separate tank for discus.

What Happens If The Water Gets Too Hot?

It would suffocate your discus.

When the water in your tank gets warmer and stays above 90 degrees for too long that reduces the amount of oxygen available, which in result will lead your fish to gasp for air near the surface of the water and eventually ie.

2. Tank Setup

a. Tank size

When it comes to tank size, most individuals want the simplest, least expensive, and quickest method to get started.

They ask what is the bare minimum discus fish tank size rather than what is the best tank size for a discus fish.

I can’t blame them for doing so, I used to do the same myself.

While that isn’t necessarily the greatest approach, it’s a human tendency. We always seek the best bang for our buck.

This technique may be successful for other things, but it’s not the greatest when it comes to discus fish.

Early savings on a tank might result in a lot of money spent later.

However, for all discus enthusiasts who don’t have the money to maintain massive tanks, there is a solution. But first, you must understand something regarding these fish.

Discus are a schooling fish. They prefer to be kept in groups. It’s not possible to keep a single discus fish alone.

Don’t get me wrong, technically, you can, but that isn’t the best way to care for discus fish.

If you’ve taken the time to read this and understand it, you’ll quickly realize that you’re not keeping a tank for a single fish; you’re keeping a tank for a group of them.

The minimum tank size for a discus fish is determined by the number of fish you want to keep.

If you start with six juveniles, for example, you’ll need at least a 55-gallon tank.

However, that’s only for growth purposes, when these juveniles become adults, then a  75-gallon tank is required. Anything less than that will be tough to maintain.

And as we all know, maintaining excellent water quality is critical to keeping these fish. It isn’t something you want to risk screwing up.

You’ve seen what’s required to keep discus in a minimal tank.

But what if you wanted to do the right thing from the start? What if you had enough money, time, and resources? What is the ideal method to go about it?

The ideal strategy is to buy 12 juvenile discus. Raise them in a grow-out tank, preferably a 75-gallon tank, and as they get older, remove the most aggressive ones.

Then, when they become adults, put them in a 100-gallon tank or a larger tank.

A general rule you can follow is one discus per 10 gallons. And it’s important to mention that since these fish are tall, do not keep them in shallow tanks.

And always put I’m your mind, the bigger the tank the better.

b. Aquarium Filter

Filtration is quite important, and no fish tank can be considered complete without it.

The truth is that the greater the degree of filtration in the fish tank, the better it is for the fish.

And due to the fact that discus fish is a messy fish, it requires one of the highest levels of filtration.

It is suggested that you have a level of filtration that is much higher than your fish tank’s size.

This clearly indicates that if your fish tank is 50 gallons, you will require a larger filter with a capacity of 100 gallons or greater or multiple filters with capacities of 50 gallons each.

From our experience, we recommend you canister filters like the UNS Delta 120 or Delta 90.

Canister filters accumulate a lot of media and, as a result, provide enough current to draw debris from the tank into the filter.

c. Heater

As we mentioned earlier, one of the most essential aspects of maintaining Discus fish is temperature.

This is due to the fact that when your Discus fish tank gets warmer, it encourages them to eat more and as a result of this, they grow larger and healthier.

The temperature in an un-planted fish tank should be kept between 82 and 86 degrees, whereas the temperature in a planted fish tank should be maintained at 80 to 82 degrees.

These are the optimal temperatures for the plants to thrive in a Discus fish tank, as well as for the Discus fish to have a good appetite and a stronger immune system.

But, why do discus fish need a heater?

Unlike mammals, discus fish have no ability to regulate their own body temperatures; therefore, they require an aquarium heater to live.

These tropical fish benefit from the use of a Discus aquarium heater for the following reasons:

  • To keep and stabilize the temperature range in the aquarium.
  • To stimulate the body of the fish’s metabolism.
  • To keep disease-causing organisms out of the aquarium tank.

Therefore, when it comes to raising Discus fish, installing a heater is very crucial and you can’t just ignore it.

d. Lighting

Don’t be surprised, but discus fish have huge eyes, which is why they require such little light since they are extremely sensitive to it.

In most situations, ambient light should be sufficient for the fish. Intense lighting, on the other hand, can harm discus fish and their health.

Despite their love of darkness, they do come from the tropics; so ensure they get 10 to 12 hours of light each day. Simply make sure it’s not too bright.

e. Tank Decorations

1. Driftwood

In their natural environment, Discus prefer to live near submerged tree roots and branches, for this reason, the best decor for Discus is Driftwood.

However, we must be cautious in our handling and selection of driftwood.

We want wood that won’t alter the pH of our tank and won’t decay or leach nutrients over time.

For this reason, Manzanita is the best wood for a Discus tank. It is clean and fits in with its natural surroundings.

Pro Tip: prepping the wood for the aquarium is a major operation that must be done.

Before adding the wood into our aquarium, we must boil driftwood for 10 to 15 minutes to remove tannins and other organic compounds.

2. Substrate

The substrate (a surface on which an organism thrives or is attached) in your planted aquarium is not only crucial to the health of your plants, but it’s also a key component of your aquarium’s ecosystem.

Keep the following in mind when preparing your substrate.

  • The size of your substrate should be appropriate. It is ideal to be between three and eight millimeters. If your grains are too tiny the roots will suffocate and crush. On the other hand, If the grain sizes are too big, there won’t be enough root contact.
  • You should be concerned that your substrate may have an impact on the water’s chemistry. Make sure your stratum will not leach minerals and salts into the water. Because many substrates are intended for other applications, such as saltwater use, you should ensure that it is safe to utilize in a discus aquarium.
  • The depth of your substrate should be deep enough for the roots of your plants, but not so deep that it takes over your aquarium. A reasonable rule of thumb is two or three inches. If you have a shallow substrate, the roots of your plants will not be able to go very far. On the other hand, there is no necessity for it to be very deep.

For your planted aquariums, we recommend using inert gravel as a substrate especially if you’re starting from scratch, because you need to be aggressive with your fertilization to keep more demanding plants healthy.

You also want to make sure the gravel is tiny enough for plant roots to grow into.

Therefore, gravel that comes from an established aquarium is an excellent choice because it contains fish mulm, which serves as a fertilizer for your beloved plants.

3. Plants

As we mentioned, discus fish adore high temperatures, and while aquarium plants are adaptable to changing conditions, heat levels this high may restrict their development.

When you want to grow a discus plant in your aquarium, the most popular option is to make a temperature compromise.

And to maintain the proper temperature for your fish, you’ll need to maintain a temperature that’s a bit lower for them but a bit higher for plants.

Keepers of experienced Discus have successfully kept their fish at 82°F or even 80°F, and some have even bred them at that temperature.

Pro Tip: to help your plant thrive, use a quality all-in-one liquid plant fertilizer such as Flourish from Seachem.

It’s not expensive and significantly increases the chance to let your plants live longer.

Our recommended plants:

f. Tankmates

Although discus are usually peaceful, they can become aggressive toward one another, especially when attempting to pair off and breed.

Most serious hobbyists avoid combining their discus with too many different species because they are sensitive to specific water parameters.

However, certain fish species can tolerate the high temperatures and low pH/hardness levels required by discus.

Cardinal tetras, neons, emperors, rummy nose tetras, clown loaches (including Apistogramma sp.), and dwarf cichlids such as rams are all excellent tankmates for discus.

Last Words

If you’re looking for a fun and colorful freshwater fish tank, the Discus is an excellent choice! 

However, keeping discus fish in your tank is not as simple as some people believe, since they require special care and specific water parameters that are different from those required by other freshwater fish.

So, if you really want a happy and healthy life for your discus, make sure you read all the following basic requirements.

We hope you have enjoyed this article as much as we did.

If you still have any questions, please share them with us in the comment section below.