Huon Aquaculture released a statement explaining that the fire melted part of the pen at its Zuidpool site, allowing 50,000 to 52,000 of the 4kg fish to escape.
"The fire damaged approximately a third of a pen, burning through and melting the pen infrastructure above and just below the waterline," the company said.
The cause of the fire remains unknown. Marine and Safety Tasmania, the Environment Protection Authority and Tasmania's Department of Primary Industries, Water and the Environment have been notified about the escape of the non-native species.
