Depending on the specific species they can be relatively easy.....I'd suggest 2 things....first which "closed brain" exactly are you considering?....second research that specific coral in a good reference book like Julian Sprungs "Corals"....
I have a type of favia that I got as a damaged/receding frag...been in my system for approximately 9 months in stable water /moderate current/above average lighting...now is 3 times the origional size and doing well.....likes to filter feed(dt's phytoplankton....and I direct feed at least once a week(after lights out).....there is a decent pic of it in the albums below.......personally I like them and find mine to be fairly easy to keep.......but I've never been able to pin point a positive ID on the one I have ....the best I've come up with is a favia sp..............