I was a bit confused at your question, but I think I get it now. You are interested in those soft corals which are brightly colores, and so far, from what you can tell, the brightly colored ones are non-photosynthetic. You are indeed right in that they are pretty difficult to take care of. They need at least daily feedings and it is important to find out what types of food they eat.
There is another option which is a hard coral, but looks much like a softie... the sun coral (Tubastrea faulkneri). It requires daily feedings, but if fed diligently, survives pretty well.
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"So God created the great creatures of the sea and every living and moving thing with which the water teems,... And God saw that it was good."
(Genesis 1:21)