With this variety the males can develop very cool 'sail fin' trailers on their dorsal fins which one has developed already. I actually have been surprised by the development of these fish with two clearly showing as males from the outset but then two others took much longer to show as males. So I believe there are a total of 4 males and 4 females. Hope is that all the males will develop the sail fin characteristic. But with the different hook shapes, head shapes and a big lack of information on the setiger silver dollars in general, I question if these are all actually 'Setiger'. Though they all have a very cool pinkish red color coming in which does make them seem as if the same variety.