OK, this is what I would do. Go to Home Depot and get a 44 gallon trash barrel. Fill it with your tank water, place all live rock in there. After this is all done, THEN scoop out the CC. Get your sand of choice (live sand from SWF.com is what I have) and if it is live sand then add directly to the tank. If you buy sand that is dry, it will cloud the tank badly for a few days, even if you rinse it very well. Some say not to rinse it at all. After this new sand is all in there, place the live rock where you want it then fill the tank back up slowly so not to disturb the sand and create a cloudy water column. Good Luck, it is well worth the switch, sand is way better.