Live Rock is an absolute benefit for all saltwater aquariums. It is a living filter that will increase your success of keeping marine life ten fold over tanks that don't have it. Totoka Rock is some of the most beautiful rock we've seen. The Totoka Rock is lighter and more porous than other rock which results in great places for all micro and macro life, like beneficial bacteria and copepods, to flourish and multiply. It allows for easy stacking and can come in a variety of interesting shapes. Because it is lighter and more porous, you will get more rock than you would of some of the heavier, more solid varieties. This rock is pre-cured and ready to become a centerpiece of your aquarium display. Once collected, the rock is scrubbed down and power sprayed to remove debris. The rock is then placed on shelves where it is sprayed down with saltwater in order to allow many of the unwanted "pests" to crawl into the tanks below. Once it reaches Saltwaterfish.com it is rinsed again and placed into our Live Rock Curing System.Once you receive your rock, you must re-cure the rock for at least a week. During shipping some of the beneficial bacteria will die off. Do not add this directly to an existing tank! Live Rock will often times have coral skeletons and other mineral deposits that are conducive to keeping marine life.Note: The weight listed is the total weight including packaging.