It's nice to see hobbyists stop buying animals that do poorly until they figure out why.
It would depend on where your Elegance came from. I would assume that the first two you had came from the Indo Pacific. These are very sensitive corals, but rather inexpensive. The Australian Elegance corals are much hardier, but cost a little more. The Diver's Den has one now.
The ideal set up for an Australian Elegance would be a system with a good amount of turnover so that you could keep the water clean, but not to much turbulence in the tank. I accomplish this by having the return plumbing run behind the rocks with many different discharges. This eliminates virtually any jet wash in the tank. A large protein skimmer, because Elegance corals like to eat large protein based foods. A refuge or sump to grow plenty of algae to help keep the water clean. A constant source of calcium. A good strong MH or T5 lighting system. The coral would need to be slowly acclimated to the lights by positioning it deep in the tank or away from direct intense lighting. This may be easier with MH because the amount of light changes as you move the coral horizontally or vertically. With T5's the light doesn't change much as the coral is moved horizontally. There would be no tangs, clowns, or large crustaceans in the tank. The coral would be feed meaty foods about once a week. Every once in a while I like to drop a couple of live FW feeder fish in the tank. I'm not sure if there is any true benefit to this, but it may do the coral some good to have some live prey for a change.