That tank is not "every species in the world". It looks to me like it is SPS
dominated with a few lower light corals towards the bottom. Amazing SPS
colonies in there. WOW.
I think the bulk of the TOTMs in ReefKeeping are SPS
based tanks with few if any softies. If you want to have a lot of any one thing you should stick to a genre. If you mix and match your reef you'll need more room to keep the in-fighting to a minimum, run healthy amounts of carbon and do frequent water changes.
species are more tolerant of mixing amongst their own, but there are some that will kill anything it comes in contact with. I have this little leather frag
that touched a piece of hynophora microconus (known to be lethal, don't let it touch anything type of coral) and the leather killed off a small section of the hydno. I never would have expected that. I also had a kenya tree kill an entire cap on contact.
That said, I have a smattering in my main tank. I try to keep them in zones. Leathers over here, SPS
over there, LPS
down here. Seems to be working ok so far with the exception of the losses mentioned above.