The Shiso trout aquaponics farm: A circular biowaste experiment in West Yorkshire

James Scott Vandeventer and John Lever

We recently visited the Burnt Hill Farm in Farnley Tyas – between Huddersfield and Wakefield in the Yorkshire countryside. In this exploratory research trip, we met with Jon, owner and operator of the Shiso trout aquaponics farm, who showed us the site and explained how the project is working to operationalize systematic circular practices.

Shiso is one of a relatively small number of aquaponics production businesses in the country, and its premise is simple: How can fish production and crops fed with their biowaste become a (relatively) large and a commercially viable farm?

Aerial view of the farm site

The project has taken shape over the past few years, receiving a significant kickstart from EU funding that enabled the purchase of core equipment and infrastructure. At present, there are roughly 1000 trout living at Shiso, and multiple crops are being trialed on site. But at the moment, the farm does not have a license to sell either fish or produce. Work is underway to complete an on-site fish slaughter and processing facility, where the trout will also be smoked, packaged and prepared for sale.

Once the processing building is complete, another hurdle remains: showing the Department for Environment, Food and Rural Affairs (DEFRA), the Environment Agency, and other inspectors that the farm is up to health standards. Currently, the health and safety permit has been withheld for a period of time until there is ‘proof of concept’ (which appears to mean no large-scale die-off or disease outbreak among the fish).

it is difficult not to find merit in this cautious approach, but this nonetheless means that further work to expand the Shiso aquaponics model and become commercially operational are on hold. It is also true that aquaponics, combining aquaculture fish farming with hydroponic (no-soil) crop production, is an established practice in other contexts (see, for example, the Aquaponics Association or the innovative EcoPonics project in Iceland).

During our site visit, we saw this living lab in action. The fish are grown in several tanks in one polytunnel, and are allowed more space to live than most commercial operations. Indeed, fish welfare was a key point that Jon raised when explaining his farm’s processes.

Living lab in action

Water from the bottom of the fish tanks (where waste settles) is moved into a separate tank, where it concentrates before being pumped into a separate polytunnel. There, a range of crops are grown – currently at small scale to see what works best in the system. The biowaste-rich water is timed to periodically release into plant beds, which are soil-less. Instead, small gravel beads form the beds, with arable spaces for healthy plant bacteria to form and ensure that the plant roots have the right balance of nutrients. We can attest that the tomatoes are fabulous.

The Shiso project is still ongoing, and it offers an exciting glimpse into the potential for creating a more closed-loop, circular system in the case of fish farming. There are still inputs to the system needed at present, including young fish, fish feed, and both gravel beads and coconut fibre growing pellets for plants. The infrastructure of the farm itself is also mostly sourced from linear industrial processes (PVC pipes, polythene covering, etc). More importantly, making both the trout and produce into a commercially successful farm will take time – and support from government, regulators, and consumers.

Jon, the owner emphasized that aquaponic projects – particularly at this scale – have limits and ‘Won’t feed the nation.’ Still, at Shiso the palpable spirit of do-it-yourself and a readiness to learn throughout the process mean that this project of trying something new holds promise.

Looking ahead, the farm aims to become a means for educating people and showing them where their food comes from, particularly important given the increasingly global and unsustainable supply chains that underpin the food system. As a regional approach to place-based food gathers strength, projects such as Shiso need both institutional support and financial backing to begin the urgently needed transition towards circular food economies.

We are glad for the opportunity to have visited the Shiso experiment and seen its circular approach to food production using biowaste in action. There are plenty of lessons to be learnt from this innovative project, and clear potential for developing an ongoing dialogue and collaboration amongst similar circular projects and local stakeholders across West Yorkshire. If these go ahead, capturing the learnings will be an important intervention into the local and regional foodscape.