Aquarium Live Rock Vs. Dry Rock

Saltwater aquariums (also known as marine aquariums) can bring a touch of beauty to any home, with colorful fish like clown fish and hippo tangs and beautiful sea-dwelling creatures like anemones. Marine aquariums, however, can be vastly more difficult to set up and maintain than a standard freshwater aquarium, as there are many more considerations one must take when deciding to delve into such a project. One of the more intriguing questions involved in setting up marine aquariums involves the difference between live rock and dry rock.

  1. Basics

    • Rocks are an important component to any marine aquarium, as they are not only decorative but provide shelters for the inhabitants, which can reduce potentially fatal stress. In the world of marine aquarium supplies, there are typically two rock choices: live rock and dry rock. The differences between the two are vast, and both have numerous advantages and disadvantages.

    What is Dry Rock?

    • Dry rock, or more commonly referred to as base rock, is simple rock that contains no organic matter. Slate, gravel and tuffa are common base rocks, and these are simply used as decorative structures that also provide vital shelter. There really isn't much more to it: dry rock is simply basic rocks that can be used in both marine and freshwater aquariums.

    What are the Pros and Cons of Dry Rock?

    • Dry rock, because it is simply basic rock, does not typically need to undergo special preparation besides basic cleaning before it is placed into an aquarium. Dry rocks are also considerably cheaper and can be picked up at virtually any pet store or even from outside (as long as rocks taken from outdoors are boiled first to sanitize them). But if you want to raise certain marine animals such as butterfly fish or many types of gobies, dry rock itself simply won't do.

    What is Live Rock?

    • Live rock is porous rock, often made up of long-dead coral, that serves as a medium for the housing and reproducing of many tiny organisms, like copepods, that are a vital food source for many fish like butterfly fish, gobies, shrimp and others. Live rock also provides a solid, porous ground for corals and anemones. Because live rock often ships with deceased organisms already inside it, adding it to your tank can help raise the initial ammonia levels and promote the nitrite/nitrate cycle, which is essential to the proper maintenance of a saltwater aquarium.

    What are the Pros and Cons of Live Rock?

    • Live rock is considerably more expensive and must be cured before it is added to an aquarium, meaning that the organisms inside must be acclimated to the aquarium water, a process that can take a few hours. Live rock also requires the use of a protein skimmer along with a filter; protein skimmers remove organic waste before it has the chance to break down into harmful materials, and the tiny organisms living inside of live rock produce a lot of extraneous waste.