Dont worry about the pH. As long as it is stable they will do fine. I know a lot of people who keep discus in a pH of 8.2 and on down to 5.0 with no problems at all. They can and will adapt to almost any pH value...as long as it is stable. Stability in the pH is the key. If someone else says otherwise, then I must have about 500 unhappy discus sitting in my holding tanks right now, lol.
-Ryan
-Ryan