Farming deep-sea fish in an industrial building might be the answer to how Chinese can keep live grouper on the banquet menu, with a clear conscience. Despite the declining numbers of deep-sea fish like grouper, demand has not waned. Many view this as an environmental disaster with little hope for a solution. But one company saw an ideal business opportunity that is now paying off after nearly a year of hard work. Business has been so good for Marine Culture Technology, which has its headquarters in Australia, that it plans a massive expansion in Yuen Long. The company, which set up shop in March last year, has an enclosed, environmentally friendly fish farm on the 14th floor of an industrial building in Chai Wan, breeding saltwater fish for the commercial market. It has two tanks, which now have 1,500 mouse grouper fingerlings and a few hundred leopard coral trout fingerlings that will be ready for the table in nine to 10 months. Having supplied fish to three hotel restaurants in Hong Kong, business is progressing swimmingly. And in six months another larger enclosed fish farm comprising 300 tanks will be set up. 'Farming fish in this self-contained environment will be free from disease, heavy metals and growth hormones,' said Brutus Lo Wai-sing, general manager of Marine Culture Technology. 'There will be no discharge of waste into the environment and the water is 100 per cent recyclable.' Although Mr Lo will not disclose how much the company invested in the project, he did admit the cost was high. As a result, more profitable species are bred, including mouse grouper and leopard coral trout. Humphead wrasse, a species that has been over fished, will also be bred. Wong Ming-hung, chair professor of the biology department at Hong Kong Baptist University, said water quality was very important for fish farming and a self-contained system helped. Having been to another local self-contained fish farm in Tin Shui Wai, Professor Wong believed this type of farming was becoming a trend in Hong Kong. 'Taiwan and Japan have already attempted a similar method. This is going to work in Hong Kong, especially with the pollution in the Pearl River Delta becoming more serious.' Experienced fisherman Lee Choi-wah, who is also chairman of the Hong Kong Chamber of Seafood Merchants, welcomes the technology. But he believes it is not going to be popular because he says Hong Kong customers can taste the difference between wild and farmed fish. Mr Lee said a similar unsuccessful operation had been attempted in Hong Kong. He said the mainland and Macau would be ideal markets to target. 'Mainland people cannot tell the difference in taste, but they like to order expensive fish,' he said. But Mr Lo is confident there is no difference in taste and believes people are willing to spend money when it comes to their health. Environmental group WWF welcomed the enclosed fish farm if it would reduce unsustainable fishing. WWF compiled a seafood guide in March last year to encourage people to choose sustainable seafood.