An urgent trial to help save an ancient fish from extinction is yet to secure all the cash needed, a month before work is due to start.
Tasmania's salmon industry in September said it would partner with Australia's fisheries research body in a major initiative to artificially boost oxygen levels in Macquarie Harbour.
The harbour is the only place where the maugean skate still exists. But it's barely hanging on and is threatened by poor water quality associated with salmon farming and other uses.
Recent conservation advice by the federal government's independent Threatened Species Scientific Committee called for urgent action before summer to ensure the species survives.
It said salmon farming was the most important anthropogenic contributor to the oxygen shortage and the fastest way to address those impacts was to significantly slash the amount of fish being farmed and fed in the harbour.
The advice also listed mechanical solutions to oxygenate the water as an "and/or" remedy.
The salmon industry has refused to reduce fish numbers, saying there's no evidence it will fix the harbour's problem.
Instead it announced a $6 million to $7 million trial, due to begin next month as summer begins, that will use a barge and pumps to suck up water, inject it with oxygen and release it into deep sections of the harbour.
Salmon Tasmania chief executive Luke Martin has told AAP the industry will provide just over half the cash and he anticipates the Fisheries Research and Development Corporation (FRDC), funded by taxpayers and fishing industry contributions, will provide the rest.
"We've got no reason to think it won't eventuate. But again they've got their own processes. They are a government statutory authority - wouldn't want to count the chickens."
FRDC managing director Patrick Hone has told AAP it's yet to receive a formal application for funding, but one is expected.
"Until we see that proposal and it goes to our board, I can't tell you what would happen to that," he said.
"All there is - as we are aware of - is a concept being put to us, which we are anticipating is going to come in the next 10 days, for additional funding for oxygen work on maugean skate."
The FRDC expects to consider the matter at a board meeting towards the end of this month.
But first the proposal will have to go to international and domestic experts for peer review, and to key stakeholders including the recovery team for the skate.
Dr Hone said it was reasonable to expect the FRDC would fund roughly half of the costs, given it and Salmon Tasmania have an industry partnership agreement on research and development
But Greens senator Peter Whish-Wilson says taxpayers shouldn't be footing the bill.
"Surely the industry would have had to do this anyway - in a polluted waterway of their own making - even without a critically endangered animal in the harbour?
"It simply looks like a taxpayer subsidy to improve cost effective salmon farming.
"The industry should accept the government's expert conservation advice and remove their industrial salmon farms from the harbour, giving the skate the best possible chance to avoid extinction."