For tuna ranching to continue to develop it must improve the farming environment by providing optimum water quality to the tuna. This will improve the performance of farming operations and deliver quality products to the market and ultimately maintain Australian farmed tuna’s competitive edge.

Also the next major step in the industry's sustainable expansion strategy is longer term holding (eg. 15 months). The above planned outcomes of the anti-foul project are important prerequisites to successful long-term grow out.

The need for this project is quite obvious. If the culture environment is improved by the use of this product, more than likely the following will occur:

• Increased water flow through the nets
• Reduction in weight on farming structures
• Reducing the re-suspension of sediments during rough weather
• Reducing surface area for potential pathogens
• Improving net handling techniques
• Potential to increase longevity of nets
• Reduce or eliminate the need for diving to clean equipment.
• Improve cage integrity.

This project aims to integrate and coordinate the industries approach on anti-foul treatments and ensure this meets with regulatory requirements. Furthermore, it is necessary to find out the efficacy of anti-foul treatments by monitoring key biological and farm husbandry parameters through trials on commercial farms. As mentioned previously, the research farm identified that the product tested showed promise and this combined with the industry panel work enabled the manufacturer to make the necessary alterations to formulations and make new products to improve performance in Spencer Gulf.

Economically it is important to find out how long a single treatment will provide a reduction of fouling organisms given the current operating format of the industry. The cost to treat a net is significant but if the objectives are achieved then the benefits outlined in section B3 under “Need” will outweigh the costs. This includes whether nets need to be treated every season, or whether one treatment will reduce fouling over two seasons.

There is a need to provide confidence that the active constituent found in the anti-foul treatments are not absorbed by the cultured organism (in this situation being tuna), is not found in the sediments and is not taken up by other marine organisms that are located nearby.

Finally, it is a clear objective to disseminate results to industry every step of the way by forming close links with industry. Further to this extension role, results will be published in the “Tuna Brief” which is a recognised printed or electronic short communication within the tuna industry for disseminating research results. In addition, results will be presented at open forum industry research meetings.