Grey mullet and parore fish will be introduced into the troubled Modellers Pond to take on its weed and algae problems.
But the project, which will cost $120,000 to introduce and has an annual maintenance bill of $93,000, sparked division among Nelson City councillors.
At the annual plan deliberations this week some councillors repeated calls to fill in the brackish pond during heated debate about how to clean it up.
The eventual cleanup costs agreed by the majority of councillors are well down on a proposal in the draft annual plan that had a $500,000 price tag.
The new initiative will cover the cost of the fish and some changes to the weir between the pond and sea tides with minor landscaping upgrades.
Once the annual plan is finalised next month Nelmac will clean out the pond over the winter months preparing it for its new inhabitants in spring.
A second option to fill in the pond for a one-off payment of $260,000 was marginally defeated.
Councillor Pete Rainey suggested developing an area at Monaco for modellers, filling in the Tahnunanui pond and creating a recreational space.
The council's infrastructure group manager Alec Louverdis said it would be a "big ticket" item needing extra funding and staff just to carry out a feasibility study. It would take 12 months before anything could be developed.
With the exception of councillor Tim Skinner, new councillors voted against the fish initiative.
Councillor Matt Lawrey said he did not want to spend $120,000 and the $93,000 annual operational costs "on nostalgia".
Councillor Gaile Noonan said she had found the community divided on the pond and preferred to have it filled in to create an area for everyone and not just a few.
The fish option has never been trialled before in a pond like the Modellers and Councillor Luke Acland said he could not support an idea were he had not seen evidence to back it.
But, Mayor Rachel Reese had confidence in the fish solution saying she trusted Louverdis's advice as he had consulted iwi, the Department of Conservation and Forest and Bird who all said there was no threat from the native fish species.
She also said Nelmac would not put its good business name to a flimsy idea.
Councillor Mike Ward supported the fish option. He said if it did not work the plagued pond issue could come back to council later to look at alternatives.
Councillor Ruth Copeland asked whether the pond fish could be caught by punters in a similar fashion to fish "with big moustaches" often caught as a recreational activity from canals in Amsterdam.
Louverdis told the council the fish would not be growing moustaches and council staff would be recommending people not to catch the fish and would try to deter them from doing so.
Louverdis said he was confident the fish option would work, as was Nelmac and the fish breeders.
He also said the Modellers Club had indicated it was willing to contribute to the landscaping and beautification of the area around the pond.
Skinner said he was appalled the council was spending so much time on the topic.
Deputy mayor Paul Matheson said he was appalled some councillors were supporting filling in the pond as it was an asset not just for Tahunanui, but the whole city.
- The Nelson Mail
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