Fish food feeds dispute

PUBLISHED : Friday, 06 May, 1994, 12:00am
UPDATED : Friday, 06 May, 1994, 12:00am

A NEW type of food for fish is expected to improve water quality around fish farms, but environment officials say the main pollution source still has to be tackled - fish faeces.

The new pellet feed would replace minced ''trash'' fish that raises levels of nitrogen, which can cause red tides.

The Agriculture and Fisheries Department (AFD) says the new feed, which it helped to develop, will reduce pollution by 60 per cent if it is used properly.

But the Environmental Protection Department claims a five per cent reduction is the best that can be hoped for because 90 per cent of the pollution from fish farms comes from fish faeces.

Farms keep thousands of fish in confined areas so faeces and uneaten food are concentrated, raising pollution levels.

The two departments' disagreement dates back to a Director of Audit report last November that warned the $1.7 billion effort to clean up Tolo Harbour, where many fish farms are concentrated, could backfire unless pollution from the farms was stopped.

Although the two departments were urged by Director of Audit Brian Jenney to seek common ground, they are still poles apart.

Senior aquaculture fisheries officer, Dr Patsy Wong Pat-shun, insisted the fish food was the only source of nitrogen because fish cannot produce nitrogen on their own. Introducing a new type of food was the most effective solution.

But principal environmental protection officer Dr Ellen Chan Ying-lung said a 1989 consultancy study, whose findings were accepted by the AFD, found fish feed was a minor source of the problem.

''We do support anything that will reduce the pollution problem, but we don't want people to believe it will solve the whole pollution problem,'' she said.