Now adays hard corals and soft corals too are "fragged" which means small fragments are broken off and grown from a mother colony , so very little realy needs to be taken from the wild logicaly. Lots of marine fish are bred in captivity tho it wil always be awkward because of the pelagic stage the fry go thru . most Clowns , Damsels, Banghai cardinals (mouthbrooders) Reidi and Kuda seahorses , some blennies and ive even heard of mandarin dragonettes being bred ....
many species should be left in the sea IMO Tangs and especialy the long suffering Regal tang that featured in a Disney film , these grow to over a foot and have no place in a tiny aquarium, in fact many of them act weird ans thier a schooling fish in the wild and very hostile to thier own species in small spaces .
One trys to educate on forums but sadly if Josslyn want a regal tang in a bi orb mummy is going to get him one .....its one of the reasons i walked away from Admin duties on a marine and coral keeping forum i just could not keep listening year after year to the selfish cruelty being practiced on these lovely creatures .