The occurrence of harmful algal blooms on Australian barramundi farms is an established threat that appears to be increasing in frequency and has already caused a significant economic impact to affected farms. As the Australian barramundi industry expands it is anticipated the frequency and severity of harmful algal blooms may increase. The potential cost savings from preventing or minimising the impact of a single harmful algal bloom can be significant (potentially up to $300,000 per case). This would provide an immediate return on the research investment of this project. The widespread and remote location of Australian barramundi farms limits the ability to quickly get suspect bloom samples to an appropriate analytical laboratory and receive diagnosis within a timeframe that is appropriate for response to an emergent harmful event, whereby emergency actions could be taken to minimise impact. There is a critical need for increasing awareness, further education and training, and provision of initial guideline tools to help farm staff differentiate harmful from harmless blooms and respond to these events accordingly. This first step will facilitate farms to develop monitoring programs to detect and respond to problem blooms prior to the encountering of large-scale mortality events.