My 13" male and 11" female 'hartwegi' have been paired for about 2 years and have spawned several times over that span of time. They have been quite compatible excepting the post-spawning "bash" that the female usually gets (notice the female's tail is missing a chunk - from the last spawn 3 weeks ago). But she always comes back and they "make up". Here they are preparing their usual site - a 12" diameter flower pot at one end of a 180g tank filled with other adult Paratheraps and Vieja. They basically take over one end of the tank and do their thing. I'll try to put on a follow-up video of the spawning act when that occurs.
http://www.youtube.com/watch?v=oE6K8Kp9reY&feature=channel
