First off, gold rams are a color bred strain so some of the rules don't apply to them as it would with regular rams. Generally Males are larger, their 2nd and 3rd dorsal rays are twice as long as the others. Females will often display a pinkish stomach area. Color, except for the pink, is not a way to distinguish between male and female rams, Both are extremely colorful and have the same coloration for the most part. You said you have 4 rams, watch them, if two hang out together, thats probably a pair, and if you are keeping all 4 in the same tank, your askin for trouble. The male rams are actually most tollerant of each other than females. Males will generally only show off and occassionally bite each other, however females are known to continue their assault on each other untill one is dead, and I've had it happen. Keep an eye on them and if you see what looks to be a pair, remove the other two. And this question could have easily been anwsered by a quick bit of research, and probably could have been avoided even being asked. Just next time do a bit of looking around on the net before hand.