Common name: Mermaid's Fan

General information

Udotea spinulosa, commonly known as Mermaid's Fan or Mermaid's Wine Glass, is a species of green macroalgae that is popular among saltwater aquarium enthusiasts for its unique fan-like appearance. This calcareous algae is part of the Chlorophyta phylum and is known for its ability to contribute to the stabilization of calcium carbonate structures in reef environments, which is beneficial for the overall health of the reef aquarium.

Care

Mermaid's Fan requires moderate to high lighting to thrive in an aquarium setting. It prefers strong water movement to mimic its natural habitat where it is often found in shallow, turbulent waters. This algae absorbs nutrients such as nitrates and phosphates from the water, which can help in controlling algae blooms. It is important to maintain stable calcium levels in the tank, as this species uses calcium to build its structure.

Symbiosis

While Udotea spinulosa does not have any specific symbiotic relationships that are of particular interest to reefkeepers, its role in the reef aquarium is similar to that of a functional plant in a terrestrial ecosystem. It provides oxygen through photosynthesis and can be a natural food source for herbivorous fish and invertebrates.

Habitat

Udotea spinulosa is typically found in the Caribbean Sea and the Gulf of Mexico. It inhabits shallow reef flats and back reef environments, often attaching itself to hard substrates where it can receive ample sunlight for photosynthesis.