For those with water outside the 'ideal' pH range of the lower 6's, discus can be successfully kept in higher pHs. I bought some from a breeder who breeds them in 7.0. I have even heard of at least a couple breeders who breed in 7.5-7.6, but the hatch rate is lower (not sure exactly how much lower though) and the water quality is higher (constant automatic water changes). The most important issues in water parameters are stability (not constantly changing the pH to get it to 'ideal') and high water quality (lots of water changes).

In my personal experience they do much better in planted tanks. The seem more comfortable and more confident. Plants also help increase water quality between water changes. So try with and without plants if you want and see which works better for you, your tank, and your discus.