QT/Frag tank questions and Clown q's

[Dabiz]

I am trying to determine what order I want to add stuff to my display. Are clowns more willing to host something if they are there first or the coral is there first?

 

AND

 

I hear about flow rates for reef tanks and fowlr but what about flow rates for QT tanks and frag tanks with no rock and just a HOB filter?