+1
As a rule of thumb generally no corals should touch they should be given enough room to grow out independently of neighbors, that being said there are plenty of tanks where mushrooms and zoas grow wildly all over each other with no noticeable ill effect. Just keep in mind the majority of corals have some form of defense be it stinging tentacles or chemical warfare, they can and will attack each other if given good cause, like an encroaching mushroom for example. Its actually really interesting see but you likely won't be too excited to see your precious coral fight each other to the death.
Hey Blue how did your pickups from the TSA flash sale fare in your tank, Looking good I hope?