The red tilapia, with its red body, resembles high-priced marine fish such as snapper and sea bream, and has always commanded a higher price than ordinary black tilapia. In tilapia farming, the use of all-male populations can effectively prevent over-breeding and reduce aggression, thereby increasing the total yield at harvest and bringing more profit to aquaculture. However, currently, many farmers still rely on hormones to control the sex of the fish before stocking, raising concerns about food safety. Therefore, this project aims to establish the genetic diversity of red tilapia strains in the freshwater center, and utilize existing techniques for breeding super-males and molecular selection to produce super-male red tilapia. The goals for the current year (2023) are: (1) to establish a source of sex-reversed female (XY) red tilapia, select for breeding with normal male (XY) red tilapia, and (2) use previously verified gender-related gene loci for offspring screening and breeding, and conduct genotype analysis to select super-male red tilapia offspring.