Where companies in the U.S. have produced single-coloured, neon green "GloFish" variants of the Domestic Betta, here in South-east Asia, the gene has been bred to several different strains. Due to the green colours, males of the species are referred to as Hulks, whereas the females are known as She-Hulks.
Similarly to other "GloFish," these are not injected with or doused in a dye, but genetically-modified using genes of other animals such as Jellyfish and Zoanthids. The fluorescent colours breed true.
