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. In reality, only a small percentage of people are able to follow those rules, and the rest of the world uses 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 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?
The easiest trick for keeping happy discus is to raise the water temperature. We recommend that the water temperature be between 85 and 86°F. Because discus farms keep their waters at these temperatures and it causes discomfort when we attempt to force them down to cool down. 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.
You should also consider pH and water hardness. This is a controversial issue as many people are very concerned about the recommended pH. We have found that both wild-caught discus and captive-bred discus perform well at pH levels between 6.8 to 7.6. The same applies to water hardness. Discus can tolerate soft to medium water hardness. While we haven’t had the pleasure of keeping German-bred discus yet to this day, it is known that they can tolerate higher pH and more hard 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.
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?
It’s always better to have a larger aquarium than you need. A 55-gallon tank is possible, but you will need to water change a lot. These fish grow up to 5 to 7 inches in size if they are treated properly. 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. Dogs are considered pack animals. However, many people only keep one dog and leave the rest at home. It’s not ideal, but it’s doable. Discus is the same.
However, they are schooling fish by nature and are much happier when surrounded by a large group of their own kind. Plus, as a type of cichlid, they may start to bully each other if you don’t a decent-sized group. In order to mitigate this territorial aggression, buy 10 to 12 juveniles all at the same time for your 75-gallon tank. (You want them to be approximately the same size so that no one gets outcompeted for food.) You’ll be able identify the males who are rowdy and can rehome them to the fish shop as they grow in size. You will eventually have a peaceful group of six adult discus, mostly females, with maybe one or two 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. Air stones are also recommended as the higher water temperatures can reduce the oxygen level. A water stone can reduce the possibility of low oxygen levels during summer heat.
Start with a larger juvenile discus school and then gradually remove the more aggressive ones.
Do Discus Really Need Daily Water Changes?
It depends. Water changes are necessary to eliminate waste. Therefore, the amount and frequency of water changes really varies for every aquarium. There are many factors to consider, including how big your aquarium is and how many fish you keep. As a rule of thumb, keep the nitrate levels below 40 ppm for plants and 20 ppm if you have 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. In general, discus are slow feeders, so if you put them with speedy, bullet-shaped fish (like barbs or even huge schools of tetras), the discus will tend to lose that race. Even other hot water fish like clown loaches, German blue rams, and angelfish can be too fast for them.
Consider starting with a discus-only tank, where they will be the main fish. After they are eating well, you can gradually add cardinal tetras and Sterbai cory catsfish to the tank, or a bristlenose pleco. Avoid having too many tank mates as the discus could lose their nutrition.
Cardinal Tetras are a popular tankmate for discus tanks but they don’t outcompete discus for food.
What’s the Best Food to Eat for Discus Fish?
Most people feed them foods that are way too big, not realizing that discus mouths are quite small. 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. We’ve had good luck with prepared foods like Hikari Vibra Bites, Sera Discus Granules, Tetra Discus Granules, and Hikari Discus Bio-Gold. Others include live or frozen brine shrimp, blackworms or microworms, as well as freeze-dried or live blackworms.
Why Are Discus Fish so Expensive?
We hinted at this previously, but tank conditions must be pristine 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. 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. Don’t purchase the cheapest discus that might have quality issues or the $300 adults that could die due to your lack of experience. For the best bullying prevention, ensure that you purchase at least one group.
Keeping discus for entertainment is easier than caring for high-maintenance discus fry.
How Do You Keep Discus Fish Happy?
The main takeaway from this care guide 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. Also, don’t put their aquarium right next to the TV with lots of loud noises and flashing lights. Anything you can do to help these shy creatures feel safe will go a long way in enhancing their health and quality of life.
Don’t forget about your stress levels! 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. You can have a discus tank that is enjoyable and profitable for many years with these guidelines.
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