I had some new left over Caribsea Life Rock from a new reef tank i recently set up. I am planning on giving it to a friend. He intends to use it to make a new reef in his 8 gallon Nano reef tank. His tank has been going for a couple years now. Is it safe for him just to remove the old reef and directly replace it with the new one? It is a small tank, and has 2 clowns living in it. We don't want to cause any fatalities... any input would be appreciated.