As I said, I am pretty satisfied with this overall. Here are the main drawbacks as I saw it:
1. The rock is not cured. You get to do this. Either you have to do this for a new aquarium, or you have to have a second container in which to cure the rock. In my experience this required changing 50% of the water every day for 2 weeks, a real chore. Most of the sponges attached to the rock died. Also, I had 3 mantis shrimp. one of which made it into my system.
2. The rock is less porous than premium fiji rock, so you need about 2 lbs/gal. Also, the rock is generally approximately spherical, so it tends to stack like cannonballs.
3. It doesn't have deep purple corraline algae on it, which a lot of people equate with quality. Mine has sort of a soft lavender growth.
4. If you buy the package, they send you live sand and rock first, and then 2 or 3 weeks later when your aquarium has cycled, a clean-up crew. The live sand was underwhelming, and I did not at the time know that you need to have a 4" to 6" sandbed, so they only send you about 1/4 of what you need. If you get this, you should mix it with a 3-fold excess of "dead" sand. Also, the clean-up crew was not nearly as effective as the one I bought from GARF to replace it a few months down the road.
The main advantages of this are that the rock is environmentally sound, it comes with an increadible array of life on it including crabs, sponges, stony corals, fan worms, tunicates, caulerpa, and a number of other desirable species. Now that I have it up and running, it looks a lot better than the reef display tanks at local fish stores.
PS: I believe ALL limestone is fossilized coral.
[This message has been edited by flounder (edited 29 January 2000).]
