This paper describes die-off events on a coral reef in the South China Sea. These events are rarely observed or reported, although they are becoming increasing common as they appear to be linked to changes in climate. It is fortunate that the authors were in the right place at the right time to capture this event and its important to try and get as much information as possible. This paper could be improved if the authors provided more precise details on the site characteristics where dead fish were seen, the species and habitats affected, the exact dates and times, and any relevant weather data at these times. These details would add to the limited data from other die-off events to help understand the causes and consequences of die-off events.