CAPTION: Salaseini Likusagati, a student assistant, overlooks the grow beds at the aquaponics demonstration facility.
The Secretariat of the Pacific Community has been investigating a new food production system known as aquaponics to grow fish and vegetables at its plant nursery in Suva, Fiji.
Work began on trialling a twin grow-bed demonstration system using tilapia fish in January 2012. The system combines conventional aquaculture with hydroponics, recirculating the water.
The initiative is led by SPC’s Fisheries, Aquaculture and Marine Ecosystems Division and supported by the European Union-funded Increasing Agricultural Commodity Trade project and SPC’s Land Resources Division.
The demonstration system is being used to build capacity in aquaponics farm design and operation, and to generate valuable data to establish project viability. Students from the Fiji National University (FNU) and the University of the South Pacific assist in daily operations.
In aquaponics, the waste from fish fed on pellet feed is broken down by bacteria into nitrates, which are then taken up by the plants. The plants extract the water and nutrients they need to grow, cleaning the water, which is then pumped back into the fish tanks.
According to SPC’s Inland Aquaculture Specialist, Dr Timothy Pickering, this method allows for a larger number of crops to be planted in close proximity and fish to be grown in closed tanks.
‘It is an intensive use of a small amount of space compared to traditional agriculture or fish farming, and has minimal environmental impact because water and nutrients are recycled instead of discharged,’ he explained.
A variety of vegetables including lettuces, basil, tomatoes, capsicum, rourou, celery, strawberries and cabbages have been grown using the SPC demonstration facility.
Dr Pickering said that the aquaponics concept is very interesting for atolls, as well as being suited to farming in peri-urban areas of high islands where demand for fish is high but space and freshwater is limited.
‘Since the system is independent of the underlying soil and it recycles freshwater, it can aid with climate change adaption for low-lying atolls that have low rainfall, unfavourable soils, and saltwater intrusion into groundwater,’ he stated.
Since aquaponics does not need soil and can be set up in the consumer’s own backyard, Dr Pickering says, it offers the distinct advantage of reducing transportation costs involved in travelling to markets and makes fresh produce readily available for consumption.
‘Access to better and healthier crops in places unsuitable for traditional agriculture can improve eating habits and help reduce lifestyle diseases,’ he added.
Dr Pickering says that a number of factors must be carefully thought about when considering aquaponics. An aquaponics system requires a reliable supply of electricity to run a water pump and air bubbler, and the availability of affordable hardware materials for the construction of tanks and a greenhouse roof. The operator of the aquaponics system should understand the needs of both fish and plants, and provide daily attention to keep them healthy.
There is a wide range of possible farm designs and configurations; however, Dr Pickering says that testing is required to find out which are best suited to Pacific Island conditions.
He said that interest in aquaponics is growing in the Pacific, with a number of organisations now working to introduce the system in the region and to carry out feasibility trials.
Examples include: the establishment of an aquaponics farm in Cook Islands in August 2012 by the Pacific Islands Trade and Invest Office of the Forum Secretariat; Australian aquaponics expert Dr Wilson Lennard joining with FNU to build a commercial-sized system for aquaponics education and training in Nadi this year; recent emergence of private sector-led aquaponics projects in Tonga, American Samoa and Guam; as well as scoping studies for technical assistance from the Food and Agriculture Organization of the United Nations for aquaponics in Pacific countries like Samoa, Kiribati and Tuvalu.
Moving forward, SPC is looking at establishing an atoll aquaponics trial in Marshall Islands later this year with support from the New Zealand Government, and linking this to national initiatives to combat non-communicable diseases like diabetes.
Results from the SPC demonstration facility in Suva will be shared with Pacific Island countries and territories to help them make informed decisions about the adoption of aquaponics by governments and enterprises in the future.
SPC