Goldfish come in several colors, being white, silver, gold, yellow and black, or a mixture of these colors. Coloring on top of the head does not indicate what sex your fish may be. Check the pectoral fins. These are the fins located right behind the head on each side of the jaw line. Male goldfish have more pointed fins while females are a bit more rounded. This may be difficult to distinguish unless you have other goldfish to compare with. All of your fish may be the same sex, in which you will have to look very closely. When goldfish breed, the males will develop tiny white spots on their gill plates between the eye and the pectoral fins. This is also another way to sex your goldies, but this trick only works when they are showing breeding signs.