checkerboard brawling

[Frauley/Elson <fraulels@minet.ca>]

Hi all,
I have weird one here. The ice storm left me with lone survivors of
several species. I have:
a wild ram male, sole survivor of 3 pairs, who is a psycho. He has
killed three characins and mugged a male cacatuoides his own size in the
last week. I changed him over to another tank, and he drove all his
tankmates up into the back corner floating plants. He's a tiny terror.
a Dicrossus maculatus male who is brawling with everything that doesn't
swim away fast. In his case, I added a female three days ago, and she is
being very careful about approaching him. He's in spectacular full
colour, beyond any photo I've seen, but he's a hooligan too.
 
So, these are supposed to be peaceful fish, and were harmless before our
local disaster. I've kept and spawned blue rams and never even seen 
nipping, and while D. maculatus is an exciting experiment for me, I've
kept D filamentosus with no problems or aggro. Has anyone else out there
seen this kind of thing with usually placid cichlids? I'm not looking
for solutions (they're easy enough), just observations.
- -Gary