Look at the pic I posted. There is a significant difference between the two. The male is the one on the left, the much larger one. With little to no red on him except for the crimson collor on his belly. The female is bright red.
Just Add water. They will spawn like clockwork. But be warned. Any fish that come into their disarm sure will be tore up. Don't let their size fool you. They are mean. Here is their 20l tank that they rule by themselves.
Full tank shot.
Female with eggs.
See what I mean by allot of eggs. Its covered lol.