Aragacrete live rock is actually easy to make, and if put into an establshed system, it doesnt take long to "cure", since its not already inhabited with life to die off in our systems, its just a matter of having it become biologically available to the life to live in, cutting they "curing" process in half and without the ammonia spike of adding uncured live rock. Actually, any material used, no matter how pourous it is, will in fact be populated with nitrifying bacteria on its available surface area rather quickly if placed under "aged" saltwater. The reason that live rock does the job that it does, isn't because of its surface area at all, it's simply the fact that the water osmoses completely through the rock itself, and within semi-solid rock, there can be very little air, creating a perfect environment for denitrification. This also can mean that sometimes the bigger the piece of rock, the better nitrification abilities of the rock. The arguement is that i've heard so far is that live rock is no doubt good, but is there anything better? Well, I believe that there is not. And this is why...
Live rock does what it does simply because it is what it is, like Popeye. Most live rock is made from almost pure calcium deposits left by thousands of years of corals, plants, and animals that have left their bones on the reef, only to petrify, and become rock so inhabited with life (including bacteria) that it actually acts as the filtration system for the entire ocean, erosion of these materials creates the sand, which also adds its benifits the entire ocean. Can there be a more perfect filtration system that what nature has created itself? No. Simply No. It took Billions of years for that system to be perfected and to become what it is now. We would only be fooling ourselves to think that we can overdo that. The question is, How can we harness the benifits of it without harming the ocean in the process? The answer to that is simply to use the system itself. Creating your own live rock, the natural way, (by putting it into the ocean and waiting) can do no harm, if anything, creating artificial reefs of concrete and other materials helps the ocean in general simply by adding to the systems available surface area for nitrifying bacteria, not to mention creating homes for thousands of animals. The oceans diversity itself decides what will live there, and what won't.
Now, I do agree that there is a sustainable harvest of live rock from the ocean, so I dont have an arguement against collecting it, as long as we replace what we take, as we take it, and allow some time for nature to catch up with us every once in a while.
Thats all I got on that. sorry so long winded.
