With your tangs, you will probably need to cover the suncoral with something when feeding them. The first suncorals I purchased weren't in the best shape. The first week I fed small amounts everyday. Once they started opening up and tentacles started growing, then I feed every other day for 2-3 weeks (been along time, can't remember exactly). Once they looked good and were healthy, I started to feed every 3 days. I do feed heavy though. I cover with an orange juice container, dice up mysis, squirt with a turkey baster. Then every 15 min. or so I give a squirt of water into the orange juice cont. to stir the mysis back up. I do that 3 or 4 times so that each head is fed at least once, usually mult. times. I leave the cont. on overnight and in the morning if there is anything left, the fish/inverts clean it up. I don't even mess with the cap for the container anymore, didn't make that much difference and it is easier without.
My hubbie got me a beautiful piece that has 3 colors or suncorals--yellow, orange, and black. I think you will enjoy them if that is the direction you decide to go in.