Live Rock provides a physical three-dimensional structure that is critical for the health and often also for the mental-emotional well-being of aquarium organisms. Live Rock habitat provides refuge and substrate that allows many organisms to live on, in and around Live Rock.


Amphipods hiding in Live Rock

Many of fish and invertebrates need a refuge to hide from other (more aggressive) organisms. Many aquarium fish and invertebrates are territorial and would "bully" others. Also some fish and invertebrates are predatory and would eat other fish and inverts if the opportunity arises. Passive and prey organisms MUST have places to hide... and Live Rock provides multiple caves, crannies and crevices that are excellent hiding places.

It is important to ensure that your Live Rock has caves and crannies of a range of sizes. Remember that a place to hide is only functional if the prey CAN go in, but the predator CAN'T. Also remember that while one organism may bully or prey others... the same organism may have to hide from others

Tiny Pods and Live rock

bigger than him/her.

Considering the size of crevices is particularly important for the well-being of amphipods (also called pods), which are small "shrimp-like" crustaceans that are a critical link in the "natural" food chain inside the aquarium. Pods feed on algae growing in your tank, but also lots of fish like to eat them (if they can catch them). Therefore providing lots of small hiding places is vital to have a large and robust standing stock of pods in an aquarium.

Ophiuroids hiding under Wild Live Rock


Many species of algae and corals need a hard substrate to grow on. In fact, in mature aquariums every inch of the available substrate will get cover with algae and corals. Although not obvious, while algae and corals are growing on the Live Rock, they are in fact sequestering nutrients from the water and fixating them into their flesh. Aquariums with lost of rock (substrate) to colonize and grow on have a larger capacity to use and reduce nitrogenous nutrients in your tank.

Food source

Above we explained how Live Rock's refuge service promotes high abundance of tiny organisms, and how its substrate service allows algae to grows on the rock. These tiny organisms are food for larger predatory fish and invertebrates, and the algae is food for herbivores.

Aquarium owners normally feed different types of foods to satisfy all the kinds of organisms in their tanks. The algae and tiny critters associated with Live Rock can be seen as "recycled food" (as opposed to the "new food" added by the aquarium owner). The more your aquarium organisms rely on "recycled food", the less you have to feed and the less you have to clean you tank (with filters, protein skimmers, etc.). More Live Rock means less maintenance.