Dam Dong Lotus Pond covering 3.5 hectares is located by Nhat Chieu Street in Quang Ba Ward. It is the largest of its kind in Hanoi.
Many people rushed to the pond to see the fish and take photos.
The Koi fish originate from Japan and are among the most expensive fish species in the world. In Vietnam, a Koi fish is sold at least VND500,000 (USD21.27).
Earlier, only lotus was grown in the pond. But lotus season lasts just around three months per year, so during the remaining time, the pond is quite polluted as the lotus fades.
However, the entry to the Koi fish area is quite narrow and lacks fencing, which poses dangers for visitors.
A pack of food for the fish is sold at around VND10,000.
