Breeding discus fish at 34 degrees Celsius is possible or not ????

The recommended water temperature is 86 degrees F or 30 degrees C. For more information see this web site.

The quality of water in your aquarium is the single most important factor in keeping you Discus healthy and happy.
Adjusting pH, by chemical means, or the alkalinity/acidity of your tank water is extremely tricky and best left to experts. Many Discus are tank bred and do very well in hard alkaline water. You can buy a simple pH testing kit from your local aquatic supplier. Display tank should have a pH of 6.5 – 7.5. For breeding purposes the pH should be 5.5 – 6.5. If greater acidity is need try adding peat to the filter medium this will gradually reduce the pH.
'Hardness' of water can be a problem in extreme cases a little peat in the filter and some driftwood in the tank should help correct this. Essential fish need to be acclimatized to your local water source.
Discus requirs slightly higher tank temperature than most freshwater tropical fish. This has to be borne in mind when procuring plants and other fish species to share their home. The temperature of a display tank for Discus fish shoulb be 27.5 to 29°C and about 30 to 33°C for breeding.