In the field of aquaculture, there’s no more vital task than providing the constant water heating or chilling required for optimum fish stock growth.

For the Huon Aquaculture Group in Tasmania, recognised globally as being the premium producer of fresh and smoked salmon products, the meeting of this key requirement is no less critical. For a recent application at one of its key hatcheries, the company through the project designer Fresh By Design turned to Rheem Australia for a specialist, large capacity chiller.

The task encompassed a total volume of 330,000 litres and 260 square metres of exposed water area to support 9,000 kg of fish. All this is maintained within 12 x 22,000-litre tanks (housed within an insulated room). The system also includes a 40,000-litre bio filter.

Rheem’s expertise in the water heating and chilling sector proved invaluable when the time came to design the facility’s water chilling system.

The demand for strict temperature control

Because the tanks support such valuable fish stock, keeping the water at the optimum temperature needed for them to survive and thrive presented a significant technical challenge.

“The project brief called for us to be able to vary the water temperatures in the tanks from seven to 14 degrees Celsius month-by-month depending on where the fish were in their growth cycle,” Rheem Pool Heating’s National Sales & Marketing Manager, Mark Crowther said.

 
“The difficulty in achieving this stems from sourcing the design and manufacture of the plant that’s going to meet that sort of performance characteristic, particularly at such low temperatures. Seven degrees is normally well beyond the scope of this type of plant.”

A specialist solution

Rheem commissioned the installation of two Accent 50 kilowatt chillers in early 2015. The Accent plants were chosen due to their great reliability, specialist design, and the fact they could be custom-built.

“In this instance, we needed to use a titanium heat exchanger because we couldn’t risk any leaching of chemicals into the water from the materials at the contact point,” Mark explained. “It’s only through Accent’s specialist engineering design and ability to custom manufacture that we were able to do this type of project. We’ve had great feedback on how well the plant is working.”

Huon Aquaculture is committed to rigorous environmental standards. The facility uses a full recirculation system, which means it reuses 95-99 per cent of the water needed, which ensures the fish live in optimum conditions and will go to sea healthy and in peak condition. The small amount of water exchanged in the hatchery each day gets used in other areas of the farm through composting, land spreading and irrigation.