Cyphastrea placement on vertical surfaces

[LardLad]

I am interested in exploring Cyphastrea. I have some nice low light/moderate flow spots on vertical rock faces.
Question; do they need to be placed flat (horizontally)?
Or can I just glue one vertically?
Also how far apart do two different species need to be?

 

[Uncle99]

They do not need to be placed horizontally.
I glued mine vertically, it spread over the disc and onto the rock work fast, slow to start though.
I don’t know it’s behavior to others.