For what its worth....I did mentioned not shocking them so they can acclimate to brighter lights..yumas can shock easy..I have shocked some myself....These two pics are of the same yuma rock. There not great pics but should show enough...
I first kept them on the bottom for about 2 months ( 1st pic ) and they only opened about 1.5 inch and didnt multiply...the second pic is about 4 inches under the water..thats only half the rock...3rd pic, other half....gone from 8 polyps to about 20 in a bout a year.....under 250w MHs....I have several others that multiply up high as well.
I also have
R. floridas I keep on the bottom for years that do fine...the tank is 30 inches deep....as I mention this is from my experiance...