Our Company

Clean Seas was formed by the Stehr Group of Companies in 2001 and was formally registered as a publicly-listed company on the Australian Securities Exchange in 2005.

As Australia’s only commercial producer of Kingfish and a recognised leader in the country’s emerging aquaculture industry, Clean Seas is globally renowned for its aquaculture produced Kingfish and is on track to increase annual production from 500 tonnes in 2012/2013 to 1,500 tonnes by 2015 in order to meet rising worldwide demand.

Clean Seas has also made progress with aquaculture-bred Southern Bluefin Tuna (SBT) and in the future looks forward to progressing research and development activities further to reach the commercial production stage.


Hiramasa Kingfish are farm raised to the highest environmental standards by its producer, Clean Seas; globally reputed for championing world’s best practice and exceeding stringent government regulations to ensure sustainable stocks for the future.

Significantly Clean Seas is the first aquaculture company in the Southern Hemisphere to be certified by the internationally-recognised sustainability accreditation, Friend of the Sea, which assesses and audits seafood operations in over 50 countries.

Hiramasa Kingfish are bred naturally at a state-of-the-art hatchery using prepared feeds that reflect its natural diet composition and are then transferred to the pristine, open waters of the Spencer Gulf, where regular monitoring by dive teams ensure that optimal environmental conditions are maintained.

As one of Australia’s leading producers of sustainable seafood, Clean Seas prides itself on the rigour and integrity that sits behind the exceptional quality that is Hiramasa, The King of Kingfish.


Aquaculture Lifecycle

“As Australia’s only commercial producer of Hiramasa Yellowtail Kingfish, Clean Seas continues to play a leading role in helping satisfy the world’s appetite for premium white fish.”
Dr Craig Foster, Clean Seas CEO

Aquaculture is one of the world’s fastest growing food production sectors but more importantly, it’s a fundamental element in the global solution to provide sustainable seafood sources.

Clean Seas, producers of Hiramasa Kingfish, is proud of its reputation as a leader in aquaculture innovation and management around the world.

How it works

The Hiramasa Kingfish cycle of life commences with our precious farm-grown eggs, which are produced to exacting standards directly from our proprietary broodstock.

The eggs are carefully transferred to an incubator where they hatch just 48 hours later, at which time we help the new larvae along with a gentle bath before transferring them to our custom-designed larval rearing tanks.

For the next 21 days, the larvae enjoy a delicious diet of live rotifers and artemia (that’s sea-monkeys to you and me!) and at exactly 0.1 grams our tiny Hiramasa Kingfish are then transferred to our nursery for weaning onto specially formulated feed with ingredients that are precisely balanced for optimal nourishment.

75 days after hatching the new fingerlings, so named because they’re about the size of a human finger, are a healthy 20 grams and ready to be transferred to the crystal-clear waters surrounding South Australia’s rugged and unspoilt Eyre Peninsula.

Because our fingerlings are so highly prized by us, we choose to helicopter them in to open sea pens three times a year in September, November and February, meaning we’re always in position to deliver a consistently rich, sustainable supply of Hiramasa across every season of the year.

Finally, our Hiramasa Kingfish reside for the duration in the crisp waters of the Spencer Gulf, which are subject to free-flowing nutrients that make their way via Southern Ocean currents from the Antarctic. Which means that it can take Hiramasa Kingfish six months to reach 1kg and, depending on the time of year, anywhere between 16-24 months to achieve the highly sought after sashimi-grade size of 4+kgs.

And so the cycle of life continues.

Research & Development

Clean Seas is a fervent believer in the value of research and considers it integral to its business strategy as a means of both delivering a superior quality product and spearheading a more sustainable industry.

Its internal team’s research expertise champions nutrition, fish wellbeing, product quality and environmental ecology and collaborates extensively with world-leading research institutions including CSIRO, SARDI, Flinders University, University of Sunshine Coast and Adelaide University.

Diet formulation

Clean Seas is a world leader in developing diets that are specially formulated for Yellowtail Kingfish and maintained to ensure the highest level of fish health and wellbeing.

Its feeds are formulated to create a balance of nutrients that guarantee feed efficiency, optimal growth and superlative taste, with a focus towards reducing our dependence on marine resources.

Through collaborations with research partners, Clean Seas has halved its dependence on fish meal and fish oil in feeds, the result of which is improved sustainability of production and a reduction in its environmental footprint.

Fish wellbeing

Stress reduction is key to producing healthy, delicious fish with, as always, prevention as the best medicine. Clean Seas achieves this with an holistic approach to nutrition, selective breeding from broodstock of exceptional quality and of course exceptionally strict biosecurity controls and site management planning to ensure the aquatic and benthic environments for the fish are maintained in pristine condition.

This rigour is complemented by a health surveillance programme established by Clean Seas’ on-farm veterinarian to ensure that the occurrence of disease is curtailed and that its fish are of the highest possible quality grade.

Product quality and Production technology

Yellowtail Kingfish is a firm-fleshed high quality fish with naturally high levels of omega-3, fatty acids minerals and vitamins.

Clean Seas’ research team regularly assesses the quality of the product using the industry-recognised Quality Index Measure, which was specifically designed for Yellowtail Kingfish and includes quantitative methods that assess colour to guarantee absolute consistency.

Clean Seas has undertaken extensive research programmes on flesh biochemistry to understand the impact of pre and post-harvest husbandry, cold-chain management impact on flesh quality and the nutritional content of the fish. All of which ensures that Hiramasa Kingfish is an unparalleled eating experience and powerhouse of nutrients.

While acknowledged both in Australia and around the world for its R&D, Clean Seas continually looks at innovative means by which to improve the quality of its fish and maintain a fresher product for longer.

Environmental sustainability

Cleanseas is absolutely committed to its sustainable management practices aimed at minimising its environmental footprint by limiting the amount of organic material contributed to the environment.

Clean Seas works closely with government departments to develop policies and farming strategies that ensure aquaculture sites are monitored and managed in way that promotes the healthiest possible marine environment.

To facilitate in understanding the impact of our farming operation on the marine environment, Clean Seas has commissioned numerous studies to examine the hydrodynamic nature of our sites and to identify the fate of the organic inputs from our farming operations. This information is key for both Clean Seas and government stakeholders in the development of policies and procedures that minimise its environmental footprint.

Sites are fallowed and rotated in similar ways that farmers fallow fields and the health of the benthic environment is assessed every 6 months by independent scientists to ensure the implemented strategies have the desired outcomes.

In addition to reducing its dependence on fish meal and fish oil, Clean Seas also invests in significant research to develop feed management practices that promote the production of high quality fish while minimising the amount of feed fed to the fish and in turn reducing the organic inputs into the ecosystem. Producing Yellowtail Kingfish with the lowest FCR and the best fish in:fish out ratio standards.

Directors and Key Management


Paul Steere
Independent Non-Executive Chairman
Founding CEO of New Zealand King Salmon (NZK) (1994-2009) and Non-Executive Director since 2009. NZK listed on ASX and NZX in October 2016 , is the leading aquaculture company in NZ and the largest Chinook salmon farmer globally. Chairs and Directorships in Wine, Aviation, Education and Architectural sectors. Chairs the Remuneration and Nominations Committee.


Nick Burrows
Independent Non-Executive Director
(April 2012)
21 years (1988 – 2009) as CFO and Company Secretary of Tassal Group Limited, Australia’s largest aquaculture company. Holds a diverse range of Non-Executive Director and advisory roles. Chairs the Clean Seas Finance, Audit and Risk Management (FARM) Committee with substantial experience in similar roles.


Hagen Stehr AO
Non-Executive Director
(September 2000)
A founding Director with extensive knowledge of and experience in the fishing and aquaculture industries, having been involved in the tuna industry in Australia since 1960. A Director of Australian Tuna Fisheries Pty Ltd which is Clean Seas’ largest shareholder (9%). Holds leadership roles in a number of industry Associations.


Marcus Stehr
Non-Executive Director
(September 2000)
Marcus is a founding Director and has over 25 years of hands on experience in marine finfish aquaculture operations encompassing Tuna, Kingfish and Mulloway. Marcus is Managing Director of Australian Tuna Fisheries Pty Ltd and holds leadership roles in a number of industry Associations.


David J Head
Managing Director & CEO
(January 2016)
Over 25 years experience as a CEO, Non-Executive Director and Corporate Advisor in a wide range of industry sectors in Australia, New Zealand, Asia and Europe in public and privately owned companies. This includes Chief Executive roles at Pepsi, Lion Nathan, Calum Textile Group and Leigh Mardon Group.


Wayne Materne
CFO & Company Secretary
(August 2014)
Over 20 years experience in CFO and senior finance roles mainly in the agribusiness and manufacturing sectors with ASX listed and unlisted companies. This includes livestock, forestry and wine / viticulture with companies including Elders, SA Forestry Corporation, Southcorp and Nepenthe.

Suggested Reading from our CEO

Suggested Reading from our CEO

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The Story of a Successful Businessman