So, the glolite tetras have been chasing each other around violently and biting each other's fins. Not good behaviour. I talked to Jay at the LFS down the street, he says that he's never seen tetras do that before... but agreed that adding another one wouldn't hurt, and could help. So we have four tetras now, the new one of which is notably bigger than its companions. We're calling it Dartanian, and it's actually doing a pretty good job keeping the original three in line... while they're quite as active as before, they aren't quite as VIOLENT. I win.
Now if only I could get that shrimp tank... if nothing else, Christmas is coming up... >^.~<