I just got 15lbs of dry rock from www.reefcleaners.org, seems like nice rock. John(owner) says you can just rinse it & add it to your tank without causing a cycle. (I'm going to cure it in my Q/T tank anyway) It's normally $2.00 per lb but he's running a special(limited quantity) $1.50 per lb with free shipping if you order 50lbs, otherwise it's only $8.00 shipping.
"Rock is at it lowest price ever, everyone gets the local price of $1.50 a pound on 50 pound boxes. ($75 for 50 pounds) Limited quantities available at this price. We will be shipping rock on each of the days above to try to get it to you before Christmas. Dry rock does a lot better under the tree than live, and there is nothing like a few rocks to stack to give you or a loved one "something to play with" during your holiday."