After keeping discus for more than 2 years, I understood that there is a lot of fuss about keeping these beauties. People unnecessarily tend to get into complications as the discus fall into delicate fishes category. If things are followed in right manner, they are as hardy fish as guppy. I'm not exaggerating...this has come from my experience.
In order to get started with discus keeping one must begin with setting up the tank. Let's see the dimensions first.
Tank Dimensions
When it comes to discus, it should be "Bigger the better". Dont go for tanks with awkward shapes, stick to the rectangular tank. The height of the tank should be at least 24", this is necessary as to give them as much space as possible to have them grow vertically as well. The depth of the tank should be 18" at least which will give them enough space to turn. The length of the tank should be at least 24" in size. You can always increase the length of the tank if you wish to add more number of discus.
Decorations
For discus with smaller size (less than 4") don't add any decoration items like rocks, sand, gravel, plants. At the max one can put good quality (processed) driftwood/bog-wood. Bare-bottom tank is a convenience to discus keeper for siphoning the tank. If the tank has got decorative items, it becomes a bit difficult for keeping the tank clean. In addition to this, if decorative items are not cleaned in timely manner, they tend to develop parasites which are harmful to fishes.
Background
The pigeon blood strains (without stress bars) do well when the tank background is plain white or light blue. Backgrounds which are dark in color may stress them a bit and the discus will start to show peppering (dark spots) on body/nose or on fins.
Preparing the tank
Once the tank is prepared, wash it and clean it with potassium permanganate. Cycle the tank for at least 1-2 weeks with cycling fishes (Zebras, Tetras etc) and the tank should have appropriate bio-filter (sponge filter) installed which will cater to the tank size accordingly. This process will make sure that the tank has got beneficial bacteria colony developed in the tank which will reduce the ammonia build-up in it.
Location of the tank
The tank should be located in traffic free area where there is less movement in front of it. Try to have tank in low noise region which will make sure not to disturb discus fishes.
If above things are followed correctly and religiously, the tank aka mansion will be perfectly set for the King.