Yes, I keep discus. Here are a couple of photos:
In my experience, the most important factors for keeping discus successfully are 2x weekly water changes, compatible tankmates (I keep mine with corys and cardinals and hatchetfish only), and good mechanical filtration cleaned frequently. If your water is really hard you might consider an R/O unit for a 50/50 mix with your tapwater (that's what I did when I lived in LA), but that's really not as important as the large, frequent water changes. I do mine with a Python system right into the tank, because we still use chlorine here instead of chloramines. If your water department has made the switch, however, I'd treat and store your change water in garbage cans or rubbermaid bins for a couple of days prior to using it.
BTW, when discus are healthy, they will eat just about anything. Mine survive on Tetra color bits, freeze-dried bloodworms, and Aquarian flakes.