including a breeding pair of bamboo sharks, two rays and some other fish .
The park said the event was caused by human error, and that the employees involved would receive disciplinary action and that procedures would be reviewed additional sensors installed. An inquiry found that the deaths were the result of a lack of oxygen in the water which lead to the fish suffocating. Normally procedures for tank maintenance allow staff to switch of the wave generator that oxygenates the water for up to 6 hours without causing harm to the fish. In this instance it was switched off for water treatment projects to be carried out, but staff failed to then properly restart it.
Ocean Park has not made a press release available.
Source: RTHK, 14/7/2014