Common name: Red Grape Algae

General information

Rhodymenia holmesii, commonly known as Red Grape Algae or Red Bush Algae, is a species of red macroalgae that is popular among reef aquarium hobbyists for its attractive appearance and ease of care. This species is characterized by its bushy, branching structure and deep red to purplish coloration, which can add a vibrant contrast to the green hues typically found in marine aquariums.

In the wild, Rhodymenia holmesii is found in temperate waters and is often attached to rocky substrates. It is not only aesthetically pleasing but also serves as a natural nutrient exporter, helping to maintain water quality by absorbing excess nutrients such as nitrates and phosphates.

Care

Red Grape Algae is relatively undemanding and can thrive in a range of lighting conditions, from moderate to high intensity. It prefers moderate water flow, which helps to deliver nutrients and remove waste products from its surface. Regular pruning is recommended to maintain its shape and promote healthy growth.

This macroalgae is non-invasive and can be easily propagated by fragmentation, making it an excellent choice for aquarists looking to cultivate their own refugium or algae scrubber setups.

Symbiosis

While Rhodymenia holmesii does not have any specific symbiotic relationships that are of particular interest to reefkeepers, it does provide a habitat and food source for a variety of microfauna, such as copepods and amphipods, which are beneficial for the overall ecosystem of a reef tank.

Habitat

Rhodymenia holmesii is typically found in cooler marine environments, often in intertidal zones where it attaches to rocks or other hard substrates. It is adaptable to a range of depths and can be found in both shallow and deeper waters.