This is an excerpt from the above mentioned link:
How do I cure live rock? What do I need?
Curing live rock is relatively simple, but sometimes it takes a lot of patience. It can be made considerably more easy with the proper tools.
Below is a list of tools that you will need before purchasing your live rock.
* Large plastic container (big enough to hold the rock and water.
* Saltwater mix. (enough to fill the container)
* Distilled or RO water (enough to fill container)
* Stiff-bristled brush. The stiffer the better, but not metal bristles.
* Clean toothbrush.
* Screwdriver (phillips head is better)
* Plenty of towels
* Plastic tarp
* One powerhead of around 150 gph.
* Heater large enough to heat container volume.
* Measuring cup and stirring device
You will start by filling the plastic container about 1/2 to 3/4 full of purified water. Be sure to mix the correct amount of synthetic sea salt to this water. Use a large plastic spoon or something similar to stir the water until no traces of undisolved salt remain suspended. Set your heater to around 75 and place it into the container. At this point you can set up the powerhead if you wish, careful to place it at a level where it will not squirt water out of the container should some evaporation go unnoticed.
To clean your live rock you will need to set up a plastic tarp or shower curtain on the floor near your plastic container. This will be used as a surface on which to clean the live rock. You will need to clean your live rock as much as possible before it is put into your plastic tub. I recommend having all of this set up in the bathroom as spills are more than likely going to occur. The actual process of cleaning the live rock is very messy as well.
Your first step to cleaning your live rock is to manually pick off any debris that you can by hand. After removing the large pieces, you will need to use your stiff-bristled brush to scrub the rock. Do not be gentle; give the live rock the same degree of scrubbing as you would a stain on a carpet. Although small pieces may break off, this is to be expected. After you have used the brush to scrub the rock as best as you can, you will now use the toothbrush to scrub the hard to reach places and holes in the rock. Scrub with the same abrasiveness as you did with the large brush. Remember, this is a calcium-based rock, not a porcelain doll. Once you are done scrubbing you can rinse the rock off with purified water. Although I am sure you can use tap water for rinsing, I would be highly concerned that it would cause even more die off.
The next step is to remove the dead or dying things that you were unable to remove with scrubbing alone. This is where the screwdriver comes in. Use the screwdriver to dig out any roots or dead organisms that are difficult to remove. I have mainly found small, rounded, black bumps that fall into this category. Other parts that may require the use of the screwdriver are growths with blackened areas underneath them. Just pop the growth off and give the blackened area a vigorous scrubbing.
An important thing to keep in mind when cleaning your rocks is not to fall victim to the "this looks neat" syndrome. If anything is squishy, black, or soft, remove it. Do not think that leaving it on the rock will result in a nice addition to your tank. Anything squishy, soft, woody, including soft algae, has a very high chance (90% or so) of dying in your curing container and fouling the water. This will inevitably lead to more die off.
After all of your rocks are rinsed, scrubbed, picked clean, and rinsed again, you can add them to your plastic container. This is where patience is a virtue. The next step is to let the live rock sit in the plastic container for a week.
After a week, remove the live rock and inspect it. If it has no squishy, soft, or scummy parts, and smells like the ocean, then it is cured. If it has a foul smell (even slightly), then you will need to scrub it all down again, make a new batch of saltwater, and place the rock into the bucket for another week. This entire process almost never takes more than four weeks. You can test for ammonia to help see if your live rock is cured as well, but this is a sketchy assumption at best.