Pulsations were recorded every 7 days from one colony per tank on three polyps. A pulsation was defined as a full contraction cycle. Counts were taken for 30 seconds in the morning using a tally counter, with water flow pumps off to prevent interference. To minimise bias, the same observer recorded all counts. Pulsation rate (pulsations per minute) was calculated by doubling the count and averaging three replicates per colony. Xenia umbellata originates from the Red Sea.

Study location: Aquarium experiment at the University of Bremen, GermanyTreatments: 3 carbon enrichment treatments of 20 mg C/L. DOM (glucose), 2. POM (phytoplankton), 3. POM (zooplankton)Date of study: May 2022Duration of study: 28 daysSpecies information: Xenia umbellata native to the Indo-Pacific and Red Sea