You only have to worry about your ph with wild caught discus. If you get a tank bred strain from a reputable dealer (I'd highly recommend Hans), they'll be fine in almost any ph, so long as it is stable. If you get interested enough in that direction, shoot me a pm, and I'll point you to some folks who can help you with more info.For Discus, you need an acid ph of 6-6.5 and a temperature of 75-80ish. Most people say you should keep them in groups of 5-7 (odd numbers are better). You need to keep the water clean, but as long as you are doing water changes and have adequate filtration you should be good. What kind of severum would you want? (gold, red, green?) You could also make it planted which would improve water quality and look awesome (even if you want to do a low tech planted).
-Rich