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. They can be difficult to care for, and many forums will recommend that you keep your water changings at 100% per 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 have many years of experience keeping discus, both at home and in the fish store, as well as helping customers to be successful with their pets. Based on our experience, this care guide provides practical advice and tips for beginners who want to start a discus tank.
What is the ideal temperature for Discus Fish?
To keep happy discus, 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. So if you want to successfully care for discus, be willing to make this necessary change, which may differ from your normal fish keeping habits.
Other environmental conditions to consider include pH and water hardness. 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 goes for water hardness. Discus can handle soft to medium-hard water. Although we haven’t yet kept German-bred discus, they are known to tolerate higher pH and harder water. These parameters are important if your goal is to breed and raise discus fry. However, they’re not as important if you just want to keep them for pleasure.
Although aquarium plants and tank mates are possible for discus aquariums, they must be capable of handling the required hot water temperatures.
What Size Tank Do You Need for Discus?
A larger aquarium is always better. We recommend a 75-gallon or larger tank. A 55-gallon tank is possible, but you will need to water change a lot. Remember that these fish get big, usually 5 to 7 inches in diameter if you’re doing things right. Also, by heating up the tank, their metabolism goes up, you have to feed them more, and then more waste is created. It is why it is recommended to do frequent water changes.
Many customers ask us, “Can I keep one discus?” Technically, the answer is yes. For example, dogs are technically pack animals, yet many people keep just one and then leave them home all day by themselves. Although it is not ideal, it can be done. The same thing applies with discus.
They are schooling fish by design and will be happier if they have a larger group. As a type, cichlids can bully each other, so make sure you have enough. You can reduce this aggression by purchasing 10 to 12 juveniles for your 75 gallon tank. (You want them to be approximately the same size so that no one gets outcompeted for food.) As they get bigger, you’ll be able to identify the rowdy males and rehome them back to the fish store. Eventually, you should end up with a nice, relatively peaceful group of six adult discus with mostly females and maybe a couple of males.
As for tank setup, you can put them in a planted tank, but make sure to find plants that can tolerate high temperatures, such as anubias, java fern, bacopa, sword plants, and micro swords. Because the higher water temperature reduces oxygen levels, we recommend that you add air stones. 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 juvenile discus school and then gradually remove the more aggressive ones.
Are Discus really a need for 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. Several considerations include how large your tank is, how many fish you have, how much you feed them, and how much biological filtration (e.g., beneficial bacteria and live plants) you have. We recommend that the nitrate level be kept below 40 ppm in planted tanks, and less than 20 ppm in non-planted tanks.
Download our free infographic to help you determine the frequency of water changes for your aquarium.
What fish can be kept with Discus?
Two criteria must be met by tank mates: they must be able live in extreme temperatures and cannot compete with the discus for food. Discus are slow feeders. If they are placed with large schools of tetras or barbs, the discus will be less likely to survive. 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 tetras are a popular tank mate for discus tanks, but don’t get so many that they outcompete the discus for food.
What is the best food for discus fish?
Many people give discus mice food that is way too big. If you notice them eating large portions of food and then spitting it out and then re-eating it, it could be a problem with their food size.
Frozen bloodworms look great as they are small and easy to eat. But discus can easily become dependent on them. You should feed them small amounts of food to ensure that they receive all the nutrients they need. Pre-prepared foods such as Hikari Vibra Bites and Sera Discus Granules or Tetra Discus Granules have been a good choice. You can also try frozen brine shrimps, freeze-dried blackworms and microworms.
Why are Discus Fish so Expensive
As we have said, tank conditions should be perfect for breeding and raising fry. It’s very time- and labor-intensive work, especially since discus take longer to reach full adult size compared to other cheaper fish like guppies. There are many options for discus to be bought from local breeders, fish shops, and even online. However, if you have never owned discus before, we advise that you stay away from extreme prices. In other words, don’t buy the cheapest ones that may have quality issues, and don’t buy the $300 adults that may die from your lack of experience. Just remember to purchase a group of them that are all the same size to minimize bullying.
Keeping discus for fun is much easier than the high-maintenance care required for breeding and raising discus fry.
How do you keep your 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. Limit the number of people near the tank and don’t let children tap on it. Keep their aquarium away from flashing lights and loud noises. Anything you can do for these timid creatures will make them feel more secure and help to improve their quality of life.
Finally, don’t forget to reduce your own stress! Many discus beginners spend too much time worrying about whether they will accidentally damage their discus. Instead of enjoying their magnificent beauty and relaxing, many people don’t realize how important it is to reduce their stress. With these simple guidelines, you’re on your way to having a successful, enjoyable discus tank for many years to come.
More blog posts similar to this one? To stay informed about the latest articles, videos and events, subscribe to our e-newsletter