Aquaponics production is emerging as an alternative for aquaculture diversification, and as ‘bio-converter’ tool to enhance the circularity in Agri-Aqua food systems. Aquaponics allows growers to save water, maximise production from their farm footprint and make productive use of nutrient-rich effluents. As a result of these benefits, commercial aquaponics farms are growing in a rate of 17%/year worldwide. However, high construction and running costs (e.g. labor, aquafeeds, electricity) are one of the main constraints for further development. The proper nutrient ratio and feed loads will dictate the size of the ‘aquaculture component’, heavily impacting the construction costs. The business profitability is also linked to establishing a market for the produce and species selection, as well as system optimization.
In 2021 CSIRO started applied research in Aquaponics with the aim of generating knowledge to help the industry grow and scale. The key focuses so far have been (i) creation of a R&D foundation and new capabilities, and (ii) establish connection, understanding and dialague with the industry. To date, three experimental trials have been conducted with barramundi (Lates calcarifer) and Jade perch (Scortum barcoo) juveniles, exploring the nursery phase (~10 to 30g as initial weights, over ~8 weeks). We evaluated the fish performance in aquaponics (AQP) versus conventional recirculating aquaculture systems (RAS); and the plant performance (butterhead lettuce Lactuca sativa, as an initial biological model) in aquaponics versus conventional hydroponics (HYD). We also explored different nutrient ratios (e.g. 1 to 3g grams of fish feed/ /plant/day) and key mineral supplementation, and their impact on the incidence of visual symptoms of plant nutrient deficiencies. The system design in RAS consisted of a fish tank, clarifier and biological filter. In AQP, similar design was applied plus a floating bed hydroponic units. In HYD, floating bed and reservoir (same fish tank) were utilised. The results demonstrated (fish and plant) performance differences according to systems, feeding ratios and mineral supplementation. We also conducted an industry survey aiming to understand the barriers of commercial aquaponics in Australia. In addition, during the past 18 months, several industry engagements were carried-out aiming to better understand the field constraints and potential needs for R&D.
Looking towards the future, a pilot-scale Aquaponics facility is being built at CSIRO and will enable research at scale, allowing us to produce and collect “real-world” data to feed into economic-sustainabilily models & Decision Support Tools.