My first tank I used crush coral as the base, I had it set up for a few
months then for reasons I still dont know, my tank died. I never figured out
how or why it happened i just knew I had no more live stock. So I quickly
replace my stock Fish for fish and sure enough they were dead within a week.
Now I just lost a few hundred dollars in the span of a few days and I'm none
too happy. I took the tank apart and did some research. There were a lot of
people I spoke with and pretty much they all had different ideas on what was
what in a reef tank.

I threw away the cruched coral and went with a 4inch sand bed mixed with
live sand, then added the LR I also invest a few$$ in a 5 stage RODI water
filter. My tank has been up for over a year and is thriving. My suggestion
is if you're starting a new tank.. do it right the first time or learn from
you mistakes. I added a link to show you how to cure ur Live rock, IT helped
me I hope it does for you too. Good luck

http://www.livestockusa.org/CURING.html