Live coral are much stronger than they look when it comes to survival. However, being transported from their natural environment will make it harder for them to adapt to new surroundings. This is why it is important to have enough information about them to make this transition easy. A lot of live coral species are also territorial and temperamental. Without the right conditions, some live coral will not survive in the aquarium. You can easily alter certain aspects of your tank to make it more accommodating for the live coral. Sometimes it is as simple as adding more light or increasing the temperature of the water.
Sometimes when live coral is not happy with their surroundings, it can be for more serious reasons that it seems. If there is a problem with the salt level or bacteria in the fish tank, it can be harder to get the live coral acclimated outside of their natural environment (mainly because you will not see immediate change in the live coral or the environment for some time). If you do see dramatic changes in the live coral, do not assume that it is dying and not do anything. Coral has a way of reviving itself when the conditions are right.
You simply have to read information on what the right conditions are of the live coral and you can alter the environment from there. The more information that you have, the easier it will be to troubleshoot to find out what it is that is causing the harm on the coral. Remember to use the information that you have on the right coral. Two corals that maybe look the same could be extremely different and need different environments to survive. Troubleshoot the specific problem with the live coral, instead of using general knowledge about the live coral. From there it should be easy to help the coral stay alive.
