A non scientific answer to a very complex question.  Dedication is my answer to a labyrinth of questions which revolve around the simple inquiry.  How does one have a mature grown  coral reef  that appears natural and healthy ?  How do I duplicate this ?  This is a question I get asked very often.  The dedication required should be the first consideration.  The life of a coral reef is greater than human life in number of years and we are at the mercy of this premise.  A complex ecosystem similar to the one in the image was created over a 10 year period and grown from all captive grown animals with zero impact in regards to removing any tangible mass from our natural oceans.
The actual time and dedication is not mentioned as often as I would like and I believe it is paramount in success and in achieving this difficult goal.  After all, we are attempting to provide a long term and stable environment for some of the most sensitive animals on earth.  A mere small temperature drift can cause mass destruction even in our natural oceans so the concept needs mention at the very least.  The fact we are dealing with captive grown animals does actually help with the genetic shifts that occur through time giving hardiness to some of these corals .  I thank the hobby and all of my supporters for listening to this.  The wise and patient reef keeper may choose using all captive grown animals and can in time achieve the goal of having a mature reef bio type of their own.  Many others will look for instant gratification in a hobby that is not designed to supply this.   The goals of the individual when attempting a artificial coral reef bio type should be considered and well thought out. And this should be done long before the first drop of sea water is mixed.  There are an infinite amount of parts to this complex question but the first one needs to be considered carefully for the rest to follow and success to be realized.