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. 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. 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. When the heat is kept high, your discus become more active, their metabolisms run well, they grow faster, and they show off better colors. 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. 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.
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 is required 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. These fish grow up to 5 to 7 inches in size if they are treated properly. Heating up the tank can increase their metabolism, which means that you need to feed them more. (That’s why people recommend doing all those frequent water changes.)
Customers often ask us if they can keep more than one discus. Dogs are considered pack animals. However, many people only keep one dog and leave the rest at home. This is possible, although it isn’t ideal. 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. 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.) 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. In the summer when the weather gets hotter than normal, an air stone can help decrease the risk of having low oxygen levels.
Start by creating a larger group of juvenile discus, then you can remove the more aggressive discus over time.
Does Discus really need daily water changes?
It depends. Remember that the purpose of water changes is to remove waste buildup. Each aquarium’s water needs will be different. 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. 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?
Two requirements must be met for tank mates to meet: they must have the ability to survive in high temperatures, and they must not outcompete discus when it comes time to eat. 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.
Instead, consider starting with a discus only tank where they are the centerpiece fish. Once you get them eating well, consider gradually adding cardinal tetras, Sterbai cory catfish, or maybe 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 can be a great choice because of their thin shape. However, discus can become addicted to them very easily. 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. 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. This is a labor-intensive and time-consuming task, particularly since discus take longer than other fish such as guppies to reach their full adult size. 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. To minimize bullying, make sure you buy a group of them.
Keeping discus for fun is much easier than the high-maintenance care required for breeding and raising discus fry.
How Do You Keep Discus Fish Happy?
The main takeaway from this care guide is to
. Make sure to heat the water, keep it stable and clean, and make sure they are properly fed. Don’t let kids tap on the glass, and limit the amount of traffic near their tank. You should also avoid placing their aquarium next to a TV that emits loud noises or flashing lights. Anything you can do for these timid creatures will make them feel more secure and help to improve their quality of life.
Last but not least, reduce your 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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