I've found Discus to be very hardy fish when healthy. To get pairs I like to keep groups of 5 to 8 in a 55 community tank. I normally do 30-50% weekly water changes for all my fish so that was no problem. I keep the temperature at 84 and they do fine. One they pair off I move them to a 20 high with a spawning cone, continue the water changes and high heat and they take care of the rest.
I've never found Discus to be the delicate challenge they're always presented as in the books as long as I practice good husbandry. I had one pair that I'd given a planted 30 along with a bunch of Kuhli loaches just as a display, and I basically forgot about that tank for nearly two months aside from feedings and topping off the water when it got too low for the undergravel fliter lift tubes to churn the surface. I was going through some serious personal issues at the time. It go to the point where most of the live plants had died, producing a nearly 2 inch thck layer of mulm at the bottom which the loaches loved. The water was so bad that when I finally did a change it stank! The pair had stopped breeding, but once I started caring for them again, picked up right here they left off.
My favorite community tank with them was a 55 with 6 Discus, 12 Congo Tetras, 3 Whiptail loricaria, and 6 corydoras julii. I got 2 pairs out of the group and they spawned and raised babies right in the community tank. It was filered by a Sandman brand hang on sand filter.
Practice good husbandry and Discus are even easier to keep than wild Tanganyikan cichlids... at least in my experience!