 A massive artificial reef is being created in Golf St Vincent in a bid to restore what once lay beneath the surface. The structure is set to not only help the environment but also recreational fishers. And nine years was given a special first look. It's hard to tell from land what this ship is doing anchored off the coast of Ardrossan but look a little closer and you'll find it's the driving force behind a breathtaking transformation. Big blocks and 850 tonnes of limestone are being dropped into the Golf 7 kilometres south of Ardrossan and will soon form a unique artificial shellfish reef. Once this reef has been built it will be the largest shellfish restoration in the southern hemisphere. This is huge for South Australia. Four million tiny oysters will be planted on the structure in a bid to turn back the clock. Other reefs once covered more than 1500 kilometres under South Australian waters, 99% of them have now disappeared. One oyster can filter four to five litres per hour and that's enough to feel about a bath tub a day. So they play a huge role in keeping the Golf clean. And it's not hard to find a local, long time fisherman who's noticed the changes. Well main thing really is the lack of fish here. There's razor fish beds that we're out just on here on this boat right where we're standing and they're nonexistent. Once everything is in place on the seafloor scientists hope the limestone and concrete will become a mature shellfish reef within two years attracting an abundance of marine species and importantly providing them with a new place to breed. And for recreational fishermen a new place to drop a line. All of those species that our recreational fishers love catching we really hope to see an increase of those stocks. It's a plan that makes sense for John Schroeder. If you've got a paddock full of feed you can fatten your lambs. The first four hectares of reef will be complete by the end of this year and be expanded to 20 hectares by 2019. Jared Brevy, Nine News.