The Acanthastrea echinata, also known as the "starry cup coral," is a species of coral in the Lobophylliidae Family. It's also a large polyp stone (LPS) coral. The thick-walled, circular corallites of the Acan can appear joined directly to one another by fused walls (cerioid) or joined by fused compound walls (subplocoid). The vertical plates in the walls (or septa) have large toothy projections. The skeleton is covered with folded, fleshy tissue. Appearing uniform in color or mottled, the Acan can be found in seemingly endless color combinations and patterns. Acans are a truly beautiful addition to any reef.
When introducing an Acan into your reef, location is important regarding lighting and waterflow. Acanthastrea echinata can be kept under a variety of light conditions ranging from low to moderate. Lighting that's too high can damage an Acan. We recommend around 100 PAR. We recommend keeping your Acan in a low to medium flow area of your reef. High flow could cause the polyps to not fully extend or could cause tears in the fleshy tissue. Lower flow also provides more opportunities for your Acan to catch a meal.
Through their symbiotic relationship with a photosynthetic algae, known as zooxanthellae, they receive many of their nutrients. They also filter-feed on the nutrients in the water column. It is a good idea to provide them with additional foods like microplankton or other foods designed for filter-feeding invertebrates. Acans benefit from targeted feeding of meaty foods. To maintain good health, calcium, strontium, and other trace elements should be monitored and added as needed.
Acan echinata are aggressive corals - even with other Acans. They need their own personal space. At night, stinging sweeper tentacles will emerge from the Acan and insure nothing is encroaching on that personal space, so make sure to give this coral room to grow and thrive.