in the imta setting seawater is recycled and up to of the wild kelp ecklonia maxima consumed by abalone is replaced by ulva lactuca grown on site in the recirculation system the overall commercial gain from using an imta approach was estimated at between usd and million per year including a significant increase in farm profits usd to the environmental benefits included the reduction of nitrogen discharges into adjacent coastal waters by to tonnes per year the reduction in harvesting of wild kelp beds by to hectares per year and the reduction of c emissions reduced pumping needs by to tonnes per year