Since you're talking about whole tank h2o2 treatments... I haven't tried this, but I was just reading about it yesterday
The "One-Two Punch" Whole Tank Algae Treatment
It actually details a very different whole tank approach. I guess just throwing it in there for your consideration.
I wasn't referring to treating the whole tank with H2O2. I was just saying that you can use 3mL/gallon while SPOT TREATING and you shouldn't see any negative effects on your fish. Any more than that and I can't guarantee that the fish won't become stressed and/or die. I stated that attempting to treat the whole tank with H2O2 simply will not have any effect on the BBA.