Hi Mike;
The more porous the rock the more surface area for beneficial bacteria to grow. If you're using a
deep sand bed though, that may not be an issue and you can use whatever rock is either more pleasing to the eye, better on the budget or more in keeping with your reefing ethics.
I have a mix of Fiji, Marshall and manmade rocks in my two tanks. I passed on the
Florida Aquacultured rock because it was so heavy and block-like although it does usually come with an amazing amount of life on it. Not all of it reef-friendly, however
but you can find hazardous critters in any type of rock.
Alice
"A BRW Original"
