Common name: Robust sea squirt

General information

Atriolum robustum, commonly known as the Sun Coral or Orange Cup Coral, is a non-photosynthetic coral species that has garnered attention in the reefkeeping community for its vibrant orange coloration and unique feeding habits. Unlike many popular reef corals, Sun Corals do not rely on symbiotic algae (zooxanthellae) for their nutritional needs and instead capture plankton and small food particles from the water column.

Care

Caring for Sun Corals requires a dedicated approach, as they need to be fed regularly with planktonic foods or finely minced seafood. They thrive in low to moderate flow areas that allow them to capture food effectively without being overwhelmed by strong currents. Since they do not depend on light for nourishment, lighting can be tailored to the needs of other tank inhabitants.

Reproduction

In the aquarium, Sun Corals can reproduce asexually through budding, where new polyps form from the base of the parent polyp. Sexual reproduction is less common in captivity but can occur with proper conditions and mature colonies.

Habitat

Naturally found in the Indo-Pacific region, Atriolum robustum prefers shaded overhangs or crevices on reef slopes where light levels are low. They can be found at various depths, often in areas that are not dominated by photosynthetic corals.