I'm no expert, just a fellow discus owner.
They prefer softer water, but not too picky. The water should be 86 F degrees. Regular water changes because discus live in the rivers of the amazon and they get freshwater constantly. If you cannot do water changes on a weekly basis, you can get away with bi-weekly changes if you get a good filter. I have a Fluval 404 and do water changes bi weekly. IF youo do get a high end canister filter, aim the output towards the glass because discus do not like strong water currents because there body acts like a sail. If you want to truly make your discus happy, float and Indan almond leaf, or use driftwood for the black water effect. This makes the water softer, and lower ph which is more close to their biotope water. Warning, this will tint your water a brown color which can be bad or good depending on you. I feed mine california black worms, Colorbit, and freeze dried brine shrimp. You may consider a shoal of bottom feeders, preferable certain corys that can tolerate very warm water because a lot of food drops to the floor when feeding discus. dont forget to supplement the cory's diet thought. They can also co exists with a school of cardinals. I find the the tetras make the discus braver in exploring the tank in the early stages of your tank. Males become extremely territorial during mating season (you can look for a thread I wrote about fighting discus).
All in all, research a lot about discus on the web. You may find a lot of information, but that doesn't mean you have to follow them exactly. Just find the information that remains consistent between different sites to add to your arsenal of knowledge.
KB