Not really the male get huge humps know as kok on the forehead. but you cant always go by that cause some females have the humps you can try to add a pics on here in hope some of the members can come up with the same answer
Not really, females typically grow slower and are longer and more pointed while males are stockier. Breeders wont sell males till around 3-4" to make sure they can tell the sex.
females will start to spawn at 2-3 inches and will do it bythemselves. Also females usually have a black spot in the dorsal fin but some may not have it at all.