One of Mr Lane's employees reported the theft to the Auckland police yesterday. It was too early for police to comment on the investigation and they were seeking more information on the theft.
The employee reportedly discovered the fish were missing when he went to feed them yesterday morning. He told police that the fish were definitely in the pond when he went to feed them on Monday, but it was completely empty yesterday.
However, Mr Lane's personal assistant at his Auckland-based Lane Capital Group told the Herald that there had been no burglary when she was contacted yesterday.
When told that police had confirmed a complaint had been received, she said she had "no idea", "no comment" and hung up.
According to last year's annual National Business Review Rich List, Mr Lane was worth $220 million.
He purchased Waimanu and several other properties in the Herne Bay area in 2005 for about $35 million.
He paid just over $11 million for Waimanu alone and brought in teams of builders, landscapers, architects and gardeners for one of the city's biggest but most hidden makeovers.
The house, based on Hawaii's Halekulani Hotel, was built by developer Graeme Soljan in 1987. The sharemarket crash forced its sale in 1990 to Scottish millionaire and former Glasgow Rangers FC owner David Murray, for $3.4 million. He sold it to the sultan in 1995 for $6.8 million.