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. 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. This care guide is based on our experience and provides useful tips and practical advice for anyone starting a discus tank.
What Is the Ideal Temperature for Discus Fish?
It is easy to keep discus happy by raising the water temperature. 85-86 degrees F is the recommended water temperature. The reason is because the discus farms we get them from usually keep their waters at these temperatures, and when we try to force them to cool down, it becomes a source of 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. If you are looking to care for discus well, it is important to be open to making this change.
You should also consider pH and water hardness. The recommended pH can be controversial since many people place great emphasis on this factor. In our experience, both wild-caught and captive-bred discus do well when the pH levels are between 6.8 and 7.6. The same thing applies with water hardness; discus are usually fine with soft to medium 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. If you’re focused on breeding and raising discus fry, you need much lower pH and water hardness, but if you’re simply keeping them for enjoyment, these two water parameters aren’t 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. You can do a 55-gallon tank, but then you’re forced to do a lot of water changes. 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. People recommend frequent water changes.
Customers often ask us if they can keep more than one discus. Although dogs are considered to be pack animals, many people just keep one dog and go home with them every day. It’s not ideal, but it’s doable. 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. 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 all to be roughly the same size so they can all compete for food. As they get bigger, you’ll be able to identify the rowdy males and rehome them back to the fish store. You should eventually end up with six adults discus with mostly females but maybe a few 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. In the summer when the weather gets hotter than normal, an air stone can help decrease the risk of having low oxygen levels.
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. 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. 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 so they will lose their race if they are paired with fast, bullet-shaped fish like barbs or huge schools of Tetras. Even hot water fish like angelfish, clown loaches, and German bluerams can be too fast to them.
You might instead start with a discus tank that only has them as the centerpiece fish. After they are eating well, you can gradually add cardinal tetras and Sterbai cory catsfish to the tank, or a bristlenose pleco. However, avoid getting too many tank mates, or else the discus may lose out on nutrition.
Cardinal Tetras are a popular tankmate for discus tanks but they don’t outcompete discus for food.
What is the best food 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. 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. Other suggestions include frozen or live brine shrimp, live or freeze-dried blackworms, and live microworms.
Why are Discus Fish so Expensive
This was something we mentioned previously. Tank conditions are essential for raising fry and breeding them. 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. Also, avoid buying the lowest quality discus, or those that are $300 more expensive, as they may be less likely to survive. 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 can you keep Discus fish happy?
The main takeaway from this care guide is to
reduce stress
. Raise the heat, keep the water clean and stable, and feed them correctly. Keep your children away from the tank, and keep them off of the glass. You should also avoid placing their aquarium next to a TV that emits loud noises or flashing lights. 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! Many novice discus owners worry too much about their discus and don’t take the time to enjoy their beautiful discus. These simple guidelines will help you have a fun and successful discus tank that lasts many years.
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