Huon Acquaculture says it's yet to determine the cause of a net tear that led to the loss of up to 130,000 small fish from one of its fortress pens in Storm Bay on Tuesday night.
CEO Peter Bender has described the loss, which follows the escape of more than 50,000 four-kilo fish in the Lower Channel last week, as "hugely concerning".
"The direction of the prevailing winds would indicate that weather is not the cause of the net tear," he said.
"In accordance with our regulatory requirements, this incident was reported to Government yesterday (Wednesday).
"Crews have continued working through the night to assess and review this incident with no clear cause identified.
"Internal investigations in relation to last week’s fire at a pen in the Lower Channel are also still ongoing with no clear cause yet identified."