Fish stocking against water pollution in China

Officials of the two eastern provinces of China announced they would release 20 million algae-eating fish into one of the country's most beautiful lakes to clean up the water.

Thai Ho is one of the most beautiful and largest freshwater lakes in China.Photo: yoyochina.net.

Thai Ho (meaning big lake) is a lake in the Yangtze River Delta, located between China's two provinces of Jiangsu and Zhejiang. With an area of ​​2,250 km2, this is one of the 4 largest freshwater lakes in China. There are about 90 islands of various sizes in the lake - from several kilometers to several kilometers.

In recent years, Thai Ho has been heavily polluted by industrial and agricultural waste. Dirty water in the lake facilitates the development of a toxic algae. The presence of algae impedes the ability of water to absorb sunlight and respiration of organisms in the lake.

According to AFP, officials in Zhejiang and Jiangsu provinces have released 10 million blue carp and white bighead to clean up the lake last February, after algae polluted the water supply for millions of people.

But water pollution in the lake causes toxic algae to flourish.Photo: mep.gov.cn.

Thai Ho management board said yesterday that about 20 million algae-eating fish will continue to be released into the lake in the next few days. The cost for fish stocking campaign is up to 1.3 million USD. The government and people have raised money for this campaign.

Each white bighead can eat 50 kg of algae and other plankton throughout its life. However, its weight only increased by 1 kg during the process.

The expansion of algae is quite common in freshwater lakes in China. The main reason that algae thrive is that untreated wastewater sources have high nitrogen levels. Nitrogen is the main ingredient in chemical fertilizers and detergents.