Haha. XD Whitney was kind of a bummer of a name to have in the last few weeks. "Are you named after Whitney Houston?"
Yeah, big fish definitely need to be double filtered. Overstocking depends on the aggression. If they really aggressive sometimes overstocking helps because there's no room to be territorial. I hope to have an African cichlid tank with Malawi peacocks, socolofi, and brichardi someday soon. Or at least, I would if I hadn't just gotten three dojo loaches that'll need a big tank when they grow up. >_> I gotta learn to walk out of pet stores without a little bag of fish.
Platies would work for the sorority too. They also drop live fry and they don't get as nippy as guppies/endlers sometimes do.