After 50% water drain & refill: FC: 7, CC: 0, pH: 7.2, Alk: 70, Cal: 340, CYA: ~20.

I held the FC at 13.5 for approx. 24 hrs. Now I'm letting it drop down to the best guess range. Also, I've stopped using the remains of my cal-hypo shock powder so I don't drive my calcium up again.

Thanks for the tips/replies.