The online fish health and water quality monitoring tool is an automated system that allows users to record key indicators of fish health which include daily fish mortalities and clinical signs of disease, as well as observations of water quality parameters that directly affect the monitored stock. The tool compiles the data automatically into an online Excel spreadsheet that can be used to refer to previous records. This online tool was developed for WorldFish breeding platforms for daily husbandry and to flag unusual mortality events. It also enables users to send automated email notifications with details of mortality reports to specific individuals if any unusual mortalities are observed. Though initially developed for daily health monitoring, the online tool can also be used to report unusual mortality events, annual health assessments and stock pre-exit health assessments before transferring fish to other facilities.