Authorities last Tuesday said the fish kill in some ponds in Batangas was due to "sulfur up-welling," particularly in Talisay town.
Residents told Bureau of Fisheries experts they were surprised upon seeing thousands of dead tilapia and bangus floating in some fishponds in Barangay Sampaloc.
Citing BFAR information, "Unang Balita" reported that officials from the agency claimed they had warned for the rise of in the concentration of sulfide in the water.
Calabarzon (Region 4-A) BFAR official said there was a "sulfur up-welling" which means that the level of toxic sulfide, coupled with the decline of oxygen in the water, caused the fishkill.
As of Wednesday morning, vendors in Talisay market were not selling bangus and tilapia.
The report also said members of the media were barred from the compound of the fish operator where the fishkill was observed.
Calabarzon-BFAR personnel claimed they observed last Saturday the water condition and warned fish cage owners about it.
But some fish farmers did not heed the warning, and those who did were able harvest their fish early. —LBG, GMA News