There Are Still Many Fish In The Kedung Ombo Reservoir That Die But Are Not As Extreme As The Quality Of The Water It Exacerbated

Photo via Antara

JAKARTA - Mass death of fish in cages in Kedung Ombo Reservoir, Boyolali Regency, Central Java, has begun to subside.

"Alhamdulillah, the mass death of thousands of fish in Kedung Ombo Boyolali has subsided," said Head of Fisheries Division of the Boyolali Regency Animal Husbandry and Fisheries Service Nurul Nugroho in Boyolali, Wednesday, January 4.

According to him, this condition was influenced by improving water quality in the Kedung Ombo Reservoir.

Based on the results of the examination, Nurul said, the water quality of the Kedung Ombo Reservoir on Tuesday (3/1) was close to normal with oxygen dissolved 4.7 mg/L, temperatures 29 to 30 degrees Celsius, and acidity levels (pH) 6-7, and nitrit levels 0.01 mg/L.

"The water has started to improve, as seen from the parameters of the water quality physically and chemically," said Nurul as quoted by Antara.

He advised cage owners in the Kedung Ombo Reservoir to increase soluble oxygen levels by using a pump and disposing of fish carcasses that were still in the pond so as not to cause new problems.

The Department of Animal Husbandry and Fisheries of Boyolali Regency together with the Center for the Laboratory for Fish Health Testing and the Environment of the Marine and Fisheries Service of Central Java Province plans to re-check the water quality of the Kedung Ombo Reservoir.

Nurul said that water quality checks were also carried out in the Cengklik Ngemplak Boyolali Reservoir to prevent the possibility of mass fish deaths.

"However, as a result of the conclusion, the waters are still good for fishery cultivation from the parameters of water quality physically and chemically," he said.

Previously, the Head of the Animal Husbandry and Fisheries Service of Boyolali Regency, Lusia Dyah Sucianti, said that fish that died in cages in the Kedung Ombo Reservoir until Tuesday (3/1) reached 200 tons. Mass fish deaths occurred in cages belonging to 37 farmers in the reservoir.

"As a result of the mass death fish incident, the loss is estimated at more than Rp. 6 billion," said Lusia Dyah Suhanti.

Mass death of fish in floating net cages in the Kedung Ombo Reservoir is caused by up-welling phenomenon or water mass reversal and decreased oxygen levels.