Cassa Bio-Tec has the sole Victorian licence to remove the starfish menace from Port Phillip Bay - using pheromones as bait.

The company has also processed tonnes of seaweed washed up at Altona, reducing landfill and preventing degradation of the beach.

Head of research and development Paul Mulard said the waste products were converted into liquid fertiliser using biodegradable enzymes.

"We've probably processed about 20,000 kilos [of seaweed] here," he said. "Our enzyme formulation turns the solid, fibrous seaweed into a liquid, and it retains all the nutrients.

"It's a world first, the way we break it down with enzymes. Ours is a total organic process."

After Hobsons Bay Council delivers the seaweed, it is washed in recycled water harvested from the factory's roof.

The sand is then returned to the beach. A batch of seaweed can be up to 40per cent sand.

"We then sort it and the seagrass gets taken out," Mr Mulard said. "We dry that and that goes to stockfeed and then we retain the seaweed and put that for further processing. What we're doing is value-adding a waste stream that was going to landfill."

Australia's National control plan for the Northern Pacific seastar states there is "abundant evidence" that the pest threatens marine biodiversity and marine industries.

With each female capable of producing up to 20million eggs a year, Mr Mulard said his firm was averting a potential environmental catastrophe.

"The starfish are attacking and eating all the native species in the bay - all the scallops, the native crustaceans - so what we're doing is cleaning up the bay at the same time.

"Because we're Victorians, we feel fantastic that this is an Australian, Victorian, concept. Obviously, we will be going worldwide. We've already been to Iceland, setting up to value-add all their fish waste. But for starfish, this is a world first right here."