Marine harmful algal blooms occur globally often impacting organisms and environments with subsequent economic losses and human health impacts. Determining potential impacts and recovery potential remains challenging for data poor species for which little biological data exist. We used citizen scientists to collect beach-washed samples for eleven priority species along with any weird or unusual fish. Specimens were identified to species and basic biological information obtained. For eleven priority species additional information on age and growth was obtained from sectioned otoliths. Likely impacts and recovery potential was estimated using two approaches, one focused on occurrence and abundance from Reef Life Survey data alongside the iNaturalist mortality data, and a second using productivity attributes from the Marine Stewardship Council framework for a productivity susceptibility analysis for fish. Almost 1000 specimens representing 15 orders, 33 families and 65 species were obtained. The most vulnerable species was the rare, solitary fish, the Whitenose Pigfish, for which little biological information is known. The site-attached Southern Blue Devil which lays benthic eggs and reaches ages of 64+ years was also considered vulnerable. A further 46 species (71% of species examined) were considered medium risk with moderate recovery potential. The remaining 17 species (26%) were considered lower risk. Overall, we filled important knowledge gaps for data-poor fishes by providing new records of age, longevity and life-history characteristics, providing an important baseline. Yet, biological data are lacking for most reef fish making it difficult to estimate life-history traits and predict recovery following harmful algal blooms.