Maybe not as much of an issue since you've taken the fish out, but use an air stone when you med or black out the tank. All that stuff is going to rot when it dies. There are several threads on here involving people with fish gasping at the surface as a result. The meds won't hurt the fish, but the low O2 or ammonia resulting from the rotting might. I got lucky that my BGA cleared up when I went to EI/CO2 (heavy on the KNO3 until the BGA left) and cut my light back a small amount.