There’s something fishy about Challenger Institute’s vegetables



Challenger Institute of Technology’s commitment to growing chemical-free produce sustainably utilising aquaponics has seen them win a Seafood Environment Award.

The pilot commercial aquaponics system has been built at Challenger’s Murdoch campus and was designed by aquaculture and aquaponics lecturer Tony Bart, in partnership with Horticulture lecturer Peter Graham and Bruce Ginbey, Aquaculture Systems Specialist at the Institute’s Australian Centre for Applied Aquaculture Research (ACAAR).

The innovative process represents a genuine cycle of sustainability, with the fish being spawned at Challenger’s hatchery in Fremantle and then grown at the Murdoch campus. The waste produced in the fish farming process is used to fertilise vegetables. These vegetables are then served at Challenger’s training restaurant, Quinlan’s.

The project was recognised when it was awarded the prestigious Western Australian Fishing Council Environment Award. It has subsequently been nominated for a National Fishing Industry Council award, to be held in Brisbane next month.

Tony defined his aquaponics system as a sustainable way of combining aquaculture and hydroponics to grow both fish and vegetables in the same system.

“It’s an environmentally sound process that reduces waste by pumping chemical-free, nutrient-rich fish water into gravel beds where plants are grown. The system uses significantly less water than is usually required for dirt-grown vegetables and is a great way of producing healthy food without the need for fertilisers,” Mr Bart explains.

“Artificial fertilisers are becoming more expensive due to the increasing cost of fossil fuels and as a result hydroponic growers are looking at alternative sources of nutrients. The waste from the fish now becomes a viable and attractive option.”

The systems being trialled are on track to produce the equivalent of 15,000 lettuces a year and 600 kg of barramundi. The system has created a great deal of interest and the Institute is presently in talks with several hydroponic growers who are seriously considering the system as a commercial venture.

Mr Bart believes there are also economic benefits to the process.

“Aquaponics is an avenue for those involved in the contract fishing industry to find alternative employment and a means of diversifying their income stream,” Mr Bart said.

ACAAR now farms barramundi year-round. The much desired table fish, flourishes in tropical conditions but is now being farmed in the winter months at Challenger’s Murdoch campus.

The system utilises alternative forms of energy, such as solar combined with insulation, to heat the water.

The solar panels generate electricity to run the submersible water pumps that pump water through the polypipe. The polypipe is coiled on the surface of the lid and solar radiation heats the water as it passes through the black heat-absorbing polypipe.

“It is an example of positively utilising a changing climate. With a greater number of sunnier days, more warmth and the use of insulation and polypiping to keep the water at a suitable temperature, the fish can thrive even through the winter months,” Mr Bart explained.

“Traditional tank filters are designed to remove the fish waste and return clean water. This system does that too but it has the added benefit of using air to clean the filters instead of water. It’s another example of how this project uses significantly less water than more traditional aquaculture and aquaponics projects.”

Reproduction and larval rearing of barramundi is relatively simple, and they are hardy and resistant to many parasites and diseases that cause problems in other commercial species of fish. Barramundi as a species is widely recognised as a premium fish within Australia and other western markets, such as the EU and North America, generally attracting good prices. In short, they are an excellent species for large scale aquaculture production.

Challenger Institute’s ACAAR cultures barramundi as required for industry, local research and development projects and for hobbyists. ACAAR can supply commercial quantities of barramundi juveniles as required and has a supply contract with Marine Produce Australia for more than one million juveniles every year.