Taking Care of Discus

Let's start by saying that this article assumes that you already have basic freshwater fish keeping knowledge, know how to use test kits, and that you want to maintain a discus show tank, and not a breeding tank.

First, we would like to dispel the common belief that you need to be some kind of "super aquarist" to keep and raise discus fish. This is simply not true. Discus are like any other fish, if you provide the proper tank, water, and feeding conditions, they will thrive, if not, they will die. It is true although that discus require a little more work on your part to ensure that they have these proper conditions, but it is certainly not something that is too hard for most people as widely believed. This article will cover some of the basics of discus keeping.

Let's take a look at what the perfect water conditions would be:-

  • pH: 5.8 to 6.2
  • Temperature: 85 degrees F
  • Ammonia: 0 ppm
  • Nitrite: 0 ppm
  • Nitrate: 0 ppm
  • Hardness: 1 degree DH (17.9 ppm)
  • Filtration: 100 percent at all times
  • Tank Size: at least 10 gallons per adult discus

Obviously, some of these conditions such as nitrate, hardness, and filtration would be very difficult to achieve in a home aquarium, without a lot of work or spending a lot of money. The goal here is to use common freshwater fish equipment in order to maintain your discus tank. Later on, you may want to purchase additional equipment to achieve more perfect conditions, especially if you are interested in breeding discus. But for now, they are really not needed. The following parameters are required for a show tank:

  1. pH: Actually, this can be from about 5.8 to 7.2. Just keep it constant! For example, if your tap water pH is 7.0, leave it as it is. You will cause more problems by adding chemicals and adjusting the pH up and down, than just leaving it alone. Discus do not like constant changes.
  2. Temperature: Use a heater around 5 watts per gallon of tank water so that you can maintain 85 degrees F without the heater working all the time.
  3. Ammonia: If your tank is properly cycled, this won't be a problem. If you don't understand this statement, read here and do not attempt to keep discus until you do.


  1. Nitrates: To keep nitrates in check it is essential to do frequent water changes. As a minimum we would recommend a 30% water change every 3 days. Also, be sure to vacuum the gravel and clean the inside of your tank glass during your water changes. Discus love clean water!
  2. Hardness: The softer the water, the better. If your water is very hard, 350 ppm or more, we would suggest adding peat to your filter. Peat will cause your water to become "tea" colored, but it will do a good job of softening the water, and also lowering the pH. Again, if the water is not in the "very hard" category, we don't recommend changing it.
  3. Filtration: We would recommend using a power filter and not an undergravel filter. Discus eats several types of foods that will become trapped under the filter, and can cause very bad water conditions. Also, be sure that you have a filter that is rated for your tank size or larger, and it will be just fine. Now, to address a very controversial topic concerning the use of carbon in your filter. Some say that you should not use carbon because it will absorb trace elements from the water required by discus and can cause a condition known as "Hole in the Head Disease". Others believe that this disease is caused by a vitamin D deficiency and not by the use of carbon.
  4. Tank size: Give them some room, they are cichlids after all, and they are territorial.

Next, let's talk about food for the discus. Variety is as important in the discus diet as it is for us human beings. We would suggest any of the following:

  1. Brine Shrimp
  2. Beef Heart
  3. Turkey Heart
  4. Daphnia
  5. Bloodworms
  6. Earthworms (small)
  7. Flake foods

A diet based on a combination of 2 or 3 of these foods will help ensure your discus is getting their proper nutrition. Discus can be pretty selective about what they will eat, so you may need to try a few different types and see how they behave. You should try to feed young discus 5-6 times a day, and adult discus 2-3 times a day.

And now finally, we would like to address a question that most new discus keepers ask:

"How many discus should I keep together?"

Well, you should never keep a discus alone in a tank. They are a social type of fish and require company. With that said, keeping two discus in a tank is also a bad idea. This usually results in the death of the smaller or weaker fish. Discus is generally a peaceful type of fish, but they are competitive over food. The stronger of the two fish will bully the other fish away from the food until it eventually quits trying to eat, and dies. Our recommendation is to keep at least 3 discus of generally the same size together. This provides the necessary social requirement, and also gives the "boss" of the tank two other fish to divide his time during feedings. He can't bully both of them at the same time and feed himself, so they all end up getting some food. If you must keep two discus in the same tank, we would suggest you purchase a clear tank divider. This will allow them to see each other, but not make contact.

We hope that this article helps in some way to assist you in your efforts to maintain a discus tank. They are very beautiful fish and deserve a good home!