A Japanese aquarium wiped out a third of its fish last week when workers â€˜cleaned' the tanks using antiseptic.
Workers at the Niigata City Aquarium incorrectly dosed the tanks with 'an antiseptic substance' after the tanks appeared 'dirty.'
Within half an hour fish had started to die leading to the eventual death toll of over 7,000 fish including sardines, damselfish and rays.
Up until the disaster, the aquarium housed 20,000 animals of around 450 species including Amur sturgeons, tarpon, Red Sea Bream and Jack Mackerel in a Sea of Japan mega fish tank, which holds 800 tons of water and Chinese Gudgeon and Japanese minnow in a tank simulating the environment of the Shinanogawa River, the longest river in Japan.
Niigata city is around 160 miles north of Tokyo on the North West coast.