Care Guide for Discus Fish – The King of the Aquarium

Discus fish are one of the most beautiful freshwater fish in the hobby, known for their spectacular colors and large, circular shape. However, they’re notorious for being extremely difficult to keep, with Internet forums often recommending strict practices like 100% water changes every day. However, these rules are only followed by a very small number of people. Most of the rest of us use more low-maintenance methods. We’ve spent many years keeping discus personally at home, caring for them in our fish store, and helping customers be successful with them. Based on our experiences, this care guide offers practical advice and useful tips for beginners starting their first discus tank.

What Is the Ideal Temperature for Discus Fish?

The easiest trick for keeping happy discus is to raise the water temperature. 85-86 degrees F is the recommended water temperature. This is because discus farms that we source them from keep their water at these temperatures. If we force them to cool off, it can cause discomfort. Your discus will be more active if the heat is high. They’ll grow faster and show better colors if their metabolisms are running well. You must be prepared to change your fish keeping habits if you want discus to thrive.

Water hardness and pH are also important environmental factors to be aware of. This is a controversial issue as many people are very concerned about the recommended pH. Our experience shows that both wild-caught and captive bred discus thrive when pH levels range between 6.8 and 7.6. The same thing applies with water hardness; discus are usually fine with soft to medium hardness. Although we haven’t yet kept German-bred discus, they are known to tolerate higher pH and harder water. You need a lower pH and a higher water hardness if you are concentrating on raising discus fry. If you keep them for enjoyment, however, these parameters won’t be as important.

It is possible to have aquarium plants or tank mates in discus tanks. However, they must be able and able to withstand the hot water temperature.

What size tank do you need for discus?

Bigger is always better, so we personally recommend a 75-gallon aquarium or larger. A 55-gallon tank is possible, but you will need to water change a lot. If you do things correctly, these fish can grow to be 5 to 7 inches tall. You can also increase their metabolism by heating the tank. This means they will eat more and produce more waste. (That’s why people recommend doing all those frequent water changes.)

Many customers ask us, “Can I keep one discus?” Technically, the answer is yes. Although dogs are considered to be pack animals, many people just keep one dog and go home with them every day. This is possible, although it isn’t ideal. Discus is the same.

They are schooling fish and they will be more happy if there is a large group. As a type, cichlids can bully each other, so make sure you have enough. In order to mitigate this territorial aggression, buy 10 to 12 juveniles all at the same time for your 75-gallon tank. To ensure that they are all equal in size, you want them to be able to compete for food. As they grow, you will be able to identify and rehome the noisy males. Eventually, you should end up with a nice, relatively peaceful group of six adult discus with mostly females and maybe a couple of males.

You can set them up in a tank. However, make sure you choose plants that are able to withstand high temperatures such as anubias and java ferns. We also recommend adding air stones since the higher water temperature decreases the amount of oxygen in the water. An air stone can be used to reduce the chance of low oxygen levels in summer, when temperatures are higher than usual.

Start with a larger school of juvenile discus and then remove the most aggressive ones over time.

Does Discus really need daily water changes?

It depends. Water changes are necessary to eliminate waste. Every aquarium is different so the frequency and amount of water changes will vary. There are several factors that you need to take into account, such as how large your tank, how many fish, how often you feed them and how much biological filter (e.g. beneficial bacteria and live plant) you have. As a general rule of thumb, we recommend keeping the nitrate level lower than 40 ppm for planted tanks and lower than 20 ppm for non-planted tanks.

To figure out how often you need to do water changes on your aquarium, get an aquarium water test kit and download our free infographic that guides you step-by-step through the process.

What fish can be kept with Discus?

Tank mates must meet two criteria: they should be able to live in high temperatures and they cannot outcompete the discus for food. Discus are slow feeders so they will lose their race if they are paired with fast, bullet-shaped fish like barbs or huge schools of Tetras. They can also be too fast for other hot water fish such as clown loaches and German blue rams.

Consider starting with a discus-only tank, where they will be the main fish. Once they’re eating well, add Sterbai Cory catfish, cardinal Tetras, and a bristlenose pleco. You should limit the number of tank mates or the discus might lose its nutrition.

Cardinal and Tetras make a great tank mate for discus tanks. However, they can’t outcompete the discus in food competition.

What’s the Best Food to Eat for Discus Fish?

People feed discus animals food that is too large, but they don’t realize that their mouths are very small. Therefore, if you see them eating the food, spitting it out, and then mouthing it again, you may have a problem with the size of the food.

Frozen bloodworms look great as they are small and easy to eat. But discus can easily become dependent on them. Make sure to feed them a wide variety of small foods to cover all the nutrients they need. Prepared foods such as Hikari Vibra Bites (Sera Discus Granules), Tetra Discus Granules (Tetra Discus Granules), and Hikari Discus Bio-Gold have proven to be very successful. You can also try frozen brine shrimps, freeze-dried blackworms and microworms.

Why is Discus Fish so expensive?

We hinted at this previously, but tank conditions must be pristine for breeding and raising fry. Because discus take longer to grow to full adult size than other fish, such as guppies, it is time-consuming and labor-intensive. Although discus can be purchased from fish shops, local breeders and online, we recommend that you avoid the extremes of price if discus are new to you. Also, avoid buying the lowest quality discus, or those that are $300 more expensive, as they may be less likely to survive. Just remember to purchase a group of them that are all the same size to minimize bullying.

Keeping discus for entertainment is easier than caring for high-maintenance discus fry.

How Do You Keep Discus Fish Happy?

This care guide’s main message is to

reduce stress

. You should raise the heat, maintain the water temperature, and give them proper nutrition. Keep your children away from the tank, and keep them off of the glass. Keep their aquarium away from flashing lights and loud noises. You can do anything you can to make these timid creatures feel secure. This will help improve their health and life quality.

Finally, don’t forget to reduce your own stress! A lot of beginner discus owners spend too much time worrying that they’ll accidentally harm their discus, instead of relaxing and appreciating their majestic beauty. These simple guidelines will help you have a fun and successful discus tank that lasts many years.

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