Welcome to the wonderful world of discus (Symphysodon discus). In this article will I describe how you can easily keep and even breed discus. The discus is a very special fish with its display of color and interesting body shape. There are many ways of setting up a functional aquarium that is suitable for discus so I will detail some of the different setups. My hope is that you will have enough information to make an educated decision about your discus tank setup. I will also point out that there are many good books written on this subject but this article is written for the Internet.
If you are thinking of starting a discus tank I would recommend starting with nothing in the tank - an empty tank without gravel or other tank decorations. It is much simpler to keep water quality standards in an empty tank and clean up is a breeze. If you do decide to have some gravel, I recommend a thin layer on the bottom of the tank so it is easy to vacuum. The size of the tank depends on how many discus you want to have, a thumb rule is about 10 gallons for one discus. For example you should not keep more than 6 adult discuses in a 55 gallon tank. To keep the temperature constant at 82-86 degrees F you will need a thermostat heater with high quality. As filter you can use biological or mechanical filters.
In this article will I go through these topics.
I have deliberately left out a diseases section because it is a complicated subject that is beyond the scope of this article.
The Discus (Symphysodon discus)
General descriptions of the two species and subspecies:
1. Symphysodon discus Heckel, 1840
2. Symphysodon aequifasciata Pellegrin, 1903 including three subspecies :
Today there are many different discus combinations on the market but each of these are from years of breeding and crossing different species with each other from the general description above. But for all discus there is the same rule of thumb concerning the general health of these fish - A healthy discus has bright and clear background color on the body and the 9 vertical bars are only shown temporarily then the fish are frighten or stressed. The back - and dorsal fins are outstretched to the maximum length then they are swimming. Also, a healthy discus should not have more than 60 breaths per minute unless they just finished eating. The forehead should be fleshy and strong, but not hollow. The eyes should also be bright and clear with intense coloring and they should be in proportion to the rest of the body. Hopefully, this information will be helpful when you decide to buy your discus. A healthy discus is very curious and follows the environment very carefully. When you go near the tank you will notice that they follow you with their eyes and come to the front of the tank to beg for food. If you come to fast or do some fast movements in front of them they will hide for a while but they will come towards you again soon. The feces from a healthy discus is brown to black and sinks like a stone to the bottom of the tank. If the feces is white or there is a white string of feces hanging out from the anal of the fish is it a sign that the fish has some kind of stomach or intestinal infection. You should never buy a fish in this condition because it is very difficult to cure them. If the fish is getting Tetra Bits as food the feces color will be bright red and sink like a stone to the bottom (own experience). A discus that is shy and hiding all time or is dark or black in color has some kind of sickness and you shall avoid buying any fish from that tank.
Don't buy a discus that has a white string of feces hanging out from the anal or if the color is dark or black, this is a sure sign of sickness
The discus tank can have all kinds of different setups depending on your personal preference. Most choose to keep their discuses in an empty tank since it is much easier to clean an empty tank. Another thing is that the discus demands high water quality and this demands frequent water changes. You can choose to have a planted tank but a empty one is much easier to keep clean and therefore also easier to keep the water at a high quality level. If you plan to have gravel, plant or roots in the tank you must have the soft acid water and the high temperature in mind. All plants do not like this.
Here are some plants you can use :
Gravel, roots and other decoration materials can you find at the pet store, don't use any other material you find in nature because there are a multitude of risks in using any foreign decoration. If you decide that you want a planted tank the bottom area should be covered with a minimum of 80% with plants. The size of the tank will be quiet big because an adult discus reaches a size of 8-9 inches. You can follow a simple thumb rule of 10 gallons per adult fish. How you place the tank is also important, not only the weight but the height also. You should place the tank about 3-4 feet above the floor so the discus have a good overview of the room and also since the temperature of the room is more stable in that height. If you have a breeding pair so can you have them in a tank of 20-30 gallons because a smaller tank them makes it easier for the fry to find their parents and the food.
What you decide to use in your tank setup is up to you - this was simply a series of suggestions based upon my experiences.
The filtration system is a very important part in all tank setups because it is here that the waste products are broken down. If it doesn't work right then the inhabitants in the tank will suffer. All living creatures including fish and microorganisms emit waste in one way or another. Because aquariums are closed systems these waste products build up and can become dangerous quick quickly. The fish produces urine and feces which will breakdown to ammonia, nitrite and eventually nitrate. This toxic waste can be removed differently like water changes, mechanical - or biological filtration. If you change the water frequently then most of the toxic waste can be removed but that's not enough. In nature there are many different micro organisms and bacteria that feed on the different waste products secreted into the water. We must find a place for these organisms and bacteria in our aquariums. An aquarium filtration system is key to providing a healthy place for these organisms to grow. The process of growing the bacteria is called cycling and it takes about 6 to 8 weeks to complete. While the tank is cycling, you should monitor ammonia, nitrite and nitrate levels. When ammonia and nitrite levels hit 0 and nitrate levels are less that 10 ppm then the tank has completed cycling. You have to be careful when add fish because the ammonia and nitrite levels may spike. This occurs because there are not enough bacteria to take care of the added bioload of the new fish. Be careful and always keep in mind that anytime you add new fish it will raise the toxic levels in an established tank.
By doing regular water changes, you can remove toxic waste very effectively. The downside to doing regular water changes is that it requires a lot of manual labor. Filtration can reduce the amount of water changes needed although it can never eliminate the need.
Mechanical Filtration provides a way to physically remove large particles from water. Filters that hang on the back of the tank provide mechanical filtration. Even canister filters that are on the outside the tank provide mechanical filtration, but they can also be used as biological filters depending of the filter material you are using. These filters have a strong flow rate so they are good at filtering away big particles in the water and feces before it has been dissolved into the water. But this kind of filter will not take away the dissolved ammonia in the water, - it will not filter away bacteria or algae either. But these filters are a good compliment to a biological filter if you use both. To be effective, the mechanical filtration media should be changed regularly to remove the large particles from the system before they become dissolved.
Methods for cleaning filters will be discussed at the end of this article.
A filter that is both good and when it comes to biological filtration is the sponge filter. The "good" bacteria grows on the sponge and is living on the waste products in the water such as ammonia and nitrite. If you don't have a biological filtration system in your tank then you need to add one. Sponge filters are very inexpensive and can be added for very little cost. If you would like to make your own sponge filter, please check our article Make Your Own Sponge Filter. Even canister filters can be used as biological filters but then you have to put a sponge on then intake tube so the big particles will not enter the filter media. Every aquarium tank needs a biological filter.
Combining a canister filter and a sponge filter is one of the most effective filtration methods I have used. The canister filter will assist the sponge filter with biological filtration. It is also important that the waste food and feces not end up in the filter since it can spoil the bacteria culture in the filter media. Every time you change the water you should also clean or replace the mechanical filter media to take the feces away. If you are using a canister filter with a pre filter or a sponge at the intake this will have to be cleaned weekly and the biological filter media should be replaced sparingly if ever since the bacteria culture can be hurt. If you need to clean a biological filter sponge, you can squeeze it in a bucket of water from your tank. If you use tap water and it contains chlorine or chloramine this will kill the "good" bacteria culture in the filter material. If this happens, you have to start the tank cycling process over again!
Even with a well functioningl filtration system the unwanted bacteria and byproducts will never be eliminated. The only effective way to remove the unwanted stuff is to do regularly water changes. In my 55 gallon aquarium with 5 discuses I change 50% of the water 2 - 3 times a week. It might sound like a lot but I almost always use frozen food. If you let leftover food and feces lay too long in water with temperatures of around 84 degrees F, it will rot and spoil the water.
Regular water changes are necessary for keeping healthy discus and to ensure the youngsters grow quickly. The easiest way to change water is to use a hose and some buckets. After you have removed the water you should not just fill up the tank with tap water again. You have to make the water suitable for the discus again, and the best way that I know how to do this is to have a separate holding tank or an old aquarium there you can prepare the water. The first goal is to remove the chlorine which is easily accomplished by aerating the water with an air tone for 24 hours. If the water also has chloramine, you will have to use a filter to get rid of the solved ammonia. During this you lower the pH to desired level. The water in the holding tank heats up to the same temp as the tank and if all the water parameters is ok you can safely fill the tank again with the prepared water.
The holding tank should be large enough to allow a quick 90% water change in your discus tank if something goes wrong or if you have used medication. With this water preparation you will also be sure that the pH - level isn't jumping up and down because it is not good for the fishes. The fish will also be less stressed since the water has the same water parameters as the show tank.
To lower the pH you can use the chemical products or the peat the pet store offer. You can buy peat at a garden center, but you have to be careful when you buy peat from a garden center because it may contain fertilizer or chemicals. I buy only natural peat from garden shops with great success.
If the water is hard you can use a Reverse Osmosis system to soften the water and lower the pH.
Some standard levels on the water that is appropriate for discus:
These are just standard levels on the water parameters and most tap water is suitable if you ventilate the water for 24 h and lower the pH before you use it.
There are two other benefits if you keep the pH below 7.0. The first benefit is that the "good" bacteria's thrives and the “bad” bacteria have their growth stunted. The second benefit is that below pH 7.0 ammonia turns to ammonium that is less toxic. As everyone knows is ammonia very toxic and not good for the health of your fish.
Every time you change your water all of the feces and leftovers must be taken away and it is better to change 10% of water each day instead of a 50% change every week. I change 50% of the water in my tank 3 times a week and my discus are healthy and also spawn regularly.
If you want to keep your discus healthy change water at least 50% of the water two times a week and keep the temperature at 84 degrees F.
The food you give to your discus is also an important aspect of raising discus. It should be nutritious and contain vitamins. The food that is available in pet shops is fine but you a brand made especially for discus. Some of these foods are Tetra Bits and Sera's Discus Flakes (I prefer this food because it doesn't have any artificial coloring added). In addition to the dry food you can use frozen food like Whattley's Discus Formula or Discus Quick. You can also make your own beefheart mix for your discus. There are many different recipes on Internet you can use. The frozen food is good for their growth and is very nutritious.
I make all of my frozen food and compliment this with dry food.
The discuses are very greedy for the first 15 - 20 minutes after that they just pick on the food and do not really eat. Therefore is it very important that you don't feed them to much so the leftovers can rot and spoil the water. Be careful then you are using the frozen food since it is very easy to spoil the water with it. If you are using the Tetra Bits the feces will be intense red, this disappear when you start to use a different food.
When you have decided to start keeping discus, please take your time. Do not rush away to the nearest pet shop and buy those they are offering you. You should check the other places also and compare the health between the different pet shops. You can also order by mail from some of the discus breeders that are online, but keep in mind that the transport should not be over 24 hours door to door. It may be well worth the time to find a breeder within driving range. If you see ads in the local paper make a call and visit them. Most people that breed discus are very serious and they will answer all of your questions. Problems can arise at the pet store because the salesman may not know much about the species. If you can bring a friend with you that has knowledge of keeping discus then it will help greatly.
If you have the space and the time and thinking of breeding the discus you should get 6 - 10 fishes that are about 9 - 10 months old. At this age the discuses start to be sexually mature and begin pairing off. You shouldn't buy only the biggest ones because the males tend to be larger than the females. It is also just about impossible to sex discus until they spawn. Once they spawn you can see that the male has a shorter and more pointed sex organ, and the female has a longer and more rounded sex organ. These things do you se just before the spawn and directly after there act.
What kind of discus you buy is up to you. It really doesn't matter since almost all discuses today are from breeders and if they are in good health it is a joy to watch them in your own discus tank. As a beginner it is wise to start with the cheap varieties until you have learned the basics. After that you can get the more expensive varieties.
This article is for people who want to start or have just started with this wonderful hobby. The article was written from my experience with the discus, reading from books and other media such as Internet. If you have any other questions, please feel free to ask them on our forums.