Originally Posted by
Deniki
I'm sorry as I'm very new to this, but "creatures" can just grow out of your live rock? So, when I do put live rock in my tank, chances are something else may come of it?
Live rock is "live" because it is taken from the oceans and kept in salt water to maintain the healthy bacteria and that provide filtration in your tank. Due to this, many times when you buy live rock you could inadvertently get an extra hitchhiker along with it. Any creature small enough to hide in the caves or holes of a piece of live rock could keep safe long enough to make it to your tank.
Common ones are snails and crabs, worms, shrimp (including mantis shrimp) etc; but as you see from this thread now and then more unusual ones manage to get through as well