Live rock abounds with life suited to the environment created in your tank. The moment you remove it from your aquarium the microorganisms that have made it their home, begin to die. This is known as ‘die-off’.
When purchasing live rock and transporting it to your newly set up aquarium, it will almost be impossible to transport in water. The longer the trip out of water between the shop and your home is, the more severe the die-off will be.
A general rule of thumb is to get the rock into water as soon as you possibly can. The longer it remains out of water, or allowed to dry, the more likely it will no longer be ‘live’.
If you have to transport live rock for an extended period, the priority is to keep the rock damp. This could be achieved with newspaper and a periodic spray of aquarium water to keep the newspaper and rock from drying out.
Ultimately, the longer the rock is out of water, the more severe the die-off will be, and the longer you will need to cure it.