You can put them on different rocks and be fine. But with my lay out either it gets along or it kills/dies lol. I have a rock wall set up so everything meshes together. I may put a mushroom on a lone rock at the bottom though, you could do the same or the other way around. But only once completely prepared! Don't keep coral until you've had fish happy and algae low for at least a month, preferably more.
Display tank - 24g nano w/ softies/montipora
I run electrical appliances underwater and enjoy injecting things with Kalk filled syringes.