My wife seen some saltwater tanks in the pet store and well now i have one. i bought a 24 gallon nano, the guy gave me live rock and live sand. i have about two inches of water and live sand on the bottom. My question is where to start. im going tonight to buy some ro water and salt mix. do i just add it and start everything up. basically is there anything i should add to the water or will the water that was in tank be enough?