Common name: Green Fern Algae

General information

Flabellia petiolata, commonly known as Green Fern Algae, is a marine plant species that belongs to the family Udoteaceae. It is not a true plant but a green macroalgae, which means it shares some characteristics with plants, such as photosynthesis, but differs in other aspects like the absence of true roots, stems, and leaves. This species is appreciated in the reefkeeping hobby for its attractive fern-like appearance and its ability to contribute to the tank's overall health by absorbing excess nutrients and providing oxygen.

Care

Green Fern Algae requires moderate to high lighting to thrive in a reef aquarium. It prefers strong water movement to mimic its natural habitat, where it is often found in shallow, wave-swept environments. Nutrient levels, particularly nitrates and phosphates, should be kept in check to prevent overgrowth, but some presence of these nutrients is necessary for the algae's growth. Regular pruning is recommended to maintain its shape and prevent it from overshadowing other inhabitants.

Symbiosis

While Flabellia petiolata does not engage in symbiosis in the same way as corals and anemones do with fish or invertebrates, it does play a crucial role in the ecosystem of a reef tank. It can act as a natural nutrient exporter, helping to maintain water quality and reduce the likelihood of nuisance algae outbreaks.

Habitat

Flabellia petiolata is native to the Mediterranean Sea and the eastern Atlantic Ocean. It typically grows on rocky substrates and in seagrass beds, often at depths where light can still penetrate effectively to allow for photosynthesis. In the aquarium, it should be anchored to live rock or another suitable substrate to simulate its natural growing conditions.