Females are bigger? It's pretty hard to breed them; they might mate and release larvae, but I read a whole bunch of threads on how people raised them. Trust me, it isn't worth the headache. Do you have java moss in the tank? Make sure there is plenty of moss. There is almost always algae in the tank. My amanos and RCS comb through the moss all day long picking out whatever algae I can't see. As a treat, once a week I boil a slice of zucchini and a leaf of spinach until the zucchini is soft and sinks. The shrimp come running for it.