Hi,
Welcome to 3reef!!!!
I wouldn't use the rock even if you boiled it to kill what ever is living in or on it. Don't start of on the wrong foot by using bad rock. Just start off by purchasing a few pounds to start off with of nice "cured" live rock at the LPS. It will help to "seed" your tank as well. I'd also invest in some live sand, either purchase it at your local pet shop or ask them for some to help start seeding your tank with beneficial bacteria to aid in cycling your tank sooner.
I don't know what you plan on keeping as far as livestock is concerned, or what type of saltwater tank you plan on replicating (REEF, FOWLR, w/Inverts), but I would do some research and and learn as much as you can about saltwater tanks and their inhabitants. Proper knowledge of equipment, livestock husbandry and compatability, proper water parameters etc. will aid you in setting up and maintaining a successful and enjoyable saltwater tank! _________ 125gal.w/Mag9.5 return(dual megaflow)>Mag7 pump Aqua Cev180skimmer.Wave2k Hamilton Reefstar(2)250watthqi(mh)pend.a Yellow, Naso Tang Red Lip Blenny Percula Clown Demoiselles Niger Trigger F. Wrasses Ceriantharia Orn.Shrimp and Stars Hermits Queen Conch asst. snails> Stars Zoos shrooms Montipora Brains Gorgonians Favia Turbinaria(large+small polyp) Acropora Xenia Tridacna (CroceaMaximaSquamosa) Leathers <35+75gal.reef tank as well>
"IF THE PHONE DOESN'T RING...IT'S ME"  jb |