Salmon returned dramatically more per hectare than any form of agriculture or other aquaculture - 2000 times more per hectare than beef or sheep meat production, he said.
To put that into perspective the "farm gate" value of an additional 700ha of salmon farms would be $1billion; another 700ha in beef and sheep production would add $500,000.
At present, Sanford produced about 3200 metric tonnes (mt) of salmon annually and 2600mt of mussels in Southland, directly employing 193 full-time-equivalent workers.
Sales of $66million were generated annually, of which about $60million was returned to the local economy through wages, salaries, operating expenses and purchases.
"From this relatively small production volume there is significant economic and social value created from a very small footprint on the water."
Mr Foggo described aquaculture in Southland as a "sleeping giant", with potential for expansion in all the species now farmed, plus blue cod, and room for many companies to be involved.
"To expand salmon farming by another 25,000mt per annum would only require 17ha of actual farm space, which is minimal. An additional 167ha would be needed, to rotationally move the farms to allow for seabed fallowing, in line with international best practice."
It had been estimated producing another 25,000mt of salmon in Southland would create up to 367 direct full-time-equivalent positions (FTEs) and 180 indirect FTEs and generate about $360million-$400million in revenue, he said.
From an employment perspective, that was close to having another New Zealand Aluminium Smelters in Southland.
Earlier this month, Mr Foggo was the guest speaker at an industry seminar attended by about 35 people including engineers, exporters, seafood processors, accountants and feedstock merchants.
In June, a group of Southlanders including Southland Mayor Gary Tong, Invercargill MP Sarah Dowie and Venture Southland enterprise and strategic projects group manager Steve Canny attended the 2016 AquaVision Conference in Stavanger, Norway.
Mr Canny said Southland could take some "pretty significant learnings from Norway", particularly in the way marine farms were consented.
"Norway has quite a mature regulatory approach. They create aquaculture zones, broadly categorised by their similar ecosystems . . . in which it is possible to undertake some type of aquaculture industry, within a very strict environment standards and reporting regime."
Companies were able to obtain "a licence for life", he said, which from an investment perspective provided them with more certainty.
The conference also discussed marine farming trends, including "pushing farms further out to sea", Mr Canny said.
Farms were being built with flexible cage structures which could be submerged when rough seas hit.
"The fish are still contained and the structure has breathing chambers so the fish can continue to do what they do until the bad weather passes. It is giving companies the ability to fish in a very effective manner. There have been phrases used like 'ocean ranching'."
However, Southland's advantage was an abundance of potential in-shore marine farm locations, and it was logical any expansion of the region's aquaculture industry would be in-shore rather than further out to sea, Mr Canny said.
The aquaculture potential for Southland - and wider New Zealand - was not only in farming fish and shellfish but in turning them into "value-added products" such as sushi and prepackaged salmon slices, Mr Canny said.
Another opportunity for Southland was to manufacture aquaculture feedstock from grain-based proteins such as wheat and oats, although that would not be economically viable until New Zealand's aquaculture industry produced at least 50,000mt-60,000mt annually, he said.
In the year to June, New Zealand seafood exports reached $1.78billion - up $201million on the previous 12 months.
Aquaculture was well regarded internationally and an exciting opportunity for New Zealand and Southland, Mr Canny said.
"Some of the leading environmental organisations in the world are advocating for it as the future of healthy-eating food protein because it's sustainable, manageable, has health and wellbeing benefits as a food, and because it produces the lowest emissions of any livestock-growing system."
