actually tang breed is pretty frequently accomplished in public aquarium. Most large gallonage public aquaria report mass spawning of their tangs frequently. Thats the problem w/ tangs, large vertical spawning accessions and mass spawning.
Oh the next problem appears to the the fry, but thats more readily solvable.
So for those interested in breeding tangs, get a job at a public aquarium and scoop out the spawn before it gets chopped up in the filters.
AS for centropyge angels fish, like flame angels -these have been done before (google frank Baensch and ReefCultureTechnologies (RCT)), however, you'll need to figure out how to get 100's to market for a reasonable price. As currently only a few are raised from each batch, and one has to sell these fish for hundreds of dollars/ea