Any rock from LR
.com is likely to come along with all kinds of assorted life because it comes straight from the ocean to you ASAP
. If it were me, I would simply save money until I could afford the best quality rock.
, the rock that is sold by most shops shouldn't qualify as live rock. It should be sold as "rock that will work as a bio-filter"
OK...so you've got a piece of rock. Put it in the tank, and get all the pumps, heaters, and skimmer going. Go and get a dead shrimp from the grocery store and throw it in there. The idea is to create lots of ammonia to seed a healthy bacteria load on that rock. Once the cycle is completed (read about tank cycling), then your tank is more ready to receive some real high quality LR