So if you want the best enviroment for the fish and are not going for looks, coralline is actually bad??
Quoted from here:
http://reefkeeping.com/issues/2004-0...ture/index.php
These vendors provide rock that often is covered with a large amount of coralline algae, and very little else. This rock is free of much of the material that can die in transit and rot in the destination tank. It is also free of most animal life. This rock can provide a beautiful backdrop or substrate in a tank, but, unfortunately, it simply can't provide much in the way of biological filtration. The small animals that moved water through the rock are not only dead and gone, but there is likely no fauna available to colonize the live rock and replace them in the destination tank. This rock is full of dead space and algae.