IMO you should water and temp acclimate everything before you put it in your tank. Drip acclimation in my opinion works the best. My LFS keeps the fish only section at a specific gravity of 1.020 and the reef section at 1.022. I keep my tank at 1.026. You need to water acclimate things to get them to slowly adjust to the salinty, ph, and nitrates in your tank. The temp is only one part of the acclimation process.
Do yourself a favor and read up on the acclimation requirments, feeding requirments, minimum tank size, lighting, water movement and if something is reefsafe or not before you buy anything. And ask here first before you take the advise of your local fish store.