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Aquaculture sector prepares to clean up its act in Mekong Delta

VIET NAM - Can Tho University has offered several proposals to clean up polluted land and waterways created by unplanned aquaculture in the Cuu Long (Mekong) Delta region.

The university said that alter-native methods of raising fish should be explored to protect the area from indiscriminate fish breeding.

Nguyen Van Thanh, director of Vinh Long Province's Department of Agriculture and Rural Development, said most farmers discharged their wastewater into nearby canals and rivers.

Because there are no deposit tanks for wastewater, farmers let the water settle to the bottom of the breeding ponds and only dredge periodically.

"If tra and basa catfish are raised inland, where will the wastewater be dumped?" Thanh added.

Figures show the total area devoted to tra and basa catfish cultivation as of August this year was 5,600ha, a tenfold increase over 2000.

Total output in the region for the year is estimated at 1.5mil tonnes, up from a mere 264,436 tonnes in 2004, which was the target set for 2010.

Tran Van Trong, deputy director of the Institute for Aquaculture Research No.2, said the limit to which the Tien and Hau rivers could ingest waste remained unknown.

He said such a limit was necessary to map out a master plan for the region's aquaculture sector.

The university's study group said the amount of feed should be lowered, which could cut production costs and minimise environmental impact.

The university's aquaculture department said it had successfully test-raised two species of catfish that could replace tra and basa catfish.

This catfish can grow easily in cages and cost less to cultivate, but provide a high yield, they said.

The fish would cost VND90,000 to VND110,000 a kilogram on the market, the group said.

The study group has also experimented with a water filtration system and diverted the treated water to rice paddies. The treated water contains nutrients that can reduce the amount of fertiliser needed for paddies.

To ensure the sustainable development of tra and basa catfish, localities should plan cultivation areas properly, and ensure that there is a clean water supply and efficient wastewater discharge, the group said.

With the price of tra and basa catfish soaring this year, sometimes going up to VND17,000 (US$1.1) a kilogram, more and more people have rushed to raise the profitable fish, according to the Viet Nam Association of Seafood Exporters and Producers.

Stringent technical trade barriers imposed by the US, Japanese and Russian markets on Vietnamese aquaculture products have already taken a heavy toll on the local industry.

The major weaknesses are substandard farming techniques, a polluted environment and unsanitary raw materials, according to the association.