OK, here's an update:
FINALLY decided to do some parameter testing and received the following:
Mag 1000
Calcium 300
dKh 9.8
So...I went ahead and dosed some calcium and magnesium. So far, the few frags I have are doing well. Some acans look pretty pissed-I assume it is because the parameters are screwy. All fishes are eating and happy without any sustained aggression. The last few days I noticed a bit of chasing, but I've been busy at work and haven't been able to feed heavy like I normally do. The auto feeder is in use; I've also been using some of the algae grazers.