Hi all. I love these fish too. I have a large BN male who has a harem of 2 breeding size females and several more coming to age soon. I have them in a comm tank and he always chooses the same place to breed, inside half a flower pot. I'm lucky and don't have to do anything special to make them spawn, they just get on with it themselves My only tip is to have heaps of wood and caves around so the male has plenty of choices for the nuptial site.
I also have around 50 BN fry in a growout tank and I've recently got some young GBAs and I hope to get a colony of them going too.