The optimal methods and anti-diseased abilities of probiotics used in aquaculture will beinvestigated. The photosynthetic bacteria (PSB) was used in organic wastewatertreatment to improve environmental quality and clarification of seawater in fishcultivation, but less used as a feed to fish larvae and zooplankton. The studies of PSBapplied in grouper seed production will be involved in this project. Meanwhile, the cobiais generally fast growing, hardy, suitable for intensive culture, and with excellentcharacteristics for processing. While a number of factors, including fish grading,transferring, and transporting might induce infections by bacteria, and have beenattributed to a measurable mass mortality during the cage culture. The vaccine toenhance resistance of cobia against pathogenic bacteria infection will be developed toreduce the uses of chemical drugs during the farming period.