Frequently Asked Questions

Why should I join OneFishTwoFish?

OneFishTwoFish helps people give back to the ocean, so their seafood consumption is more sustainable. By joining the program you’ll be helping to return more fish to the ocean. You can feel proud about doing your bit for ocean health and becoming Seafood Positive.

How does it work?

OneFishTwoFish captures fees from participating seafood restaurants and wholesalers and makes grants to selected conservation projects. The projects use the proceeds to undertake habitat restoration activities that measurably improve fish habitat and populations. Less than 10% of the fees are used by Seafood Positive to provide supporters with ocean-related news and information and to market the program to new supporters.

What's the science behind returning fish to the sea?

Our projects use two methods for returning fish to the sea: 1. Fish habitat restoration and 2. Assisted breeding (also known as fish restocking). To calculate the number of fish returned to the sea through habitat restoration, we use a simplified fisheries model based on a common scientific method (zu Ermgassen et al. 2021). Projects calculate the number and type of additional fish created at one year of age in the newly restored habitat compared to unrestored habitat. The calculations are measured over a 10 year period and we apply discounts to ensure our estimates remain conservative. For assisted breeding, we use the number of fish returned at the time of release. All projects are required to follow our detailed technical guidance document and adhere to our project standards. For a copy of the technical guidance document or for more information on how we calculate fish, please email:

How are projects selected?

Projects are chosen by undergoing a rigorous selection process that includes assessment using 10 scientific principles and 17 project criteria. These are summarised in our Technical Guidance to Voluntary Seafood Offset Projects which all projects much follow. Our project criteria and standards were developed by Dr Chris Gillies and several external scientists including from CSIRO, NSW Government Department of Fisheries, The Nature Conservancy and several universities. Our project standards are based on global biodiversity and carbon offset standards applied by hundreds of organisations and governments globally.

Do you replace fish on a like-for-like basis?

We can't replace fish on a like-for-like basis, but the initiatives we support endeavour to holistically increase fish stock in the ocean. We focus on improving coastal ecosystems and fisheries, where most of our seafood comes from, and importantly, where the ocean most needs our help. Read our FAQ 'What's the science behind returning fish to the sea' to find out more about our methods.

Why are the oceans in trouble?

Oceans suffer many threats, including pollution from land, coastal development, habitat destruction, overfishing, ocean acidification and marine plastics. Cumulatively, these threats have degraded and destroyed many marine ecosystems and caused harm to fish and marine life.

What do I receive if I join? (Business)

Businesses participating in the program receive access to project images, videos and stories from the projects, marketing collateral, logo use and invitations to special events. We also provide access to our OneFishTwoFish sustainable seafood network that connects like-minded businesses and customers.

Are there any other benefits to OneFishTwoFish?

Plenty! Habitat restoration typically has a number of other benefits beyond just creating fish and improving biodiversity. Shellfish reefs are great at using up the nutrients coming out of our rivers and estuaries. Mangroves, saltmarshes and seagrasses (known as coastal wetlands) are great at sequestering carbon and supporting a variety of bird species. Rocky reefs, like giant kelp forests, are amazing places to snorkel and dive, and support recreation and tourism. By supporting OneFishTwoFish, you'll be helping to restore these ecosystems and the many benefits they provide to people and nature.

Why was OneFishTwoFish created?

OneFishTwoFish offers a simple way for seafood consumers, retailers, restaurants and other businesses to offset their seafood consumption. Restoring marine ecosystems is one of the best ways of helping fish populations and marine life to recover. We created OneFishTwoFish to support projects that address the loss of fish and biodiversity in our oceans.

How do I know the program is genuine?

OneFishTwoFish only works with reputable organisations with a track record in successfully completing habitat restoration and assisted breeding. We also have a government and industry advisory board to ensure projects align with the latest strategies to improve ocean health. We’re committed to transparency and will post project reports and other documentation on our website so people can review outcomes for themselves.