You guys want to know why bettas fight? They're control freaks. Seriously set up a sorrority and watch what happens. They fight for control. In this tank there's enough room for all to peacefully live, several territories help. But eventually there's gonna be a bigger, meaner, tougher, male who will take complete control of the tank, should he die or be removed they'll fight. The negative....some torn fins and then the females will begin to fight each other as well.....why?? Because they will begin to establish their right to mate with the dominant male in their community...and then you'll end up with fry (possibly...the power heads might prevent succesful spawning).
BTW that first picture is amazing!! It shows beauty and grace as well as destruction.
Who am I? Well I am a Junior Member of the International Betta Congress and a breeder of white HMPKs, red dragon HMPKs, black/red dragon HMPKs, metallic multi HMPKs, blue masked HMPKs, and now multi color HMs. Soon to add black HMs. I will be showing in New Breeder class in fall of 2012.