How about looking into why the poster actually has BGA in the first place?
Then you do not need pills...........
roud:
It's not new news........and the methods to kill BGA are many and cost nothing, address the root causes.
Clean the tank well, remove what's there, water change, clean filter.
Turn light and CO2 off for 3 days, add KNO3 at 10ppm.
Cover tank with towel, trash bag etc so that no light at all get inside(you can feed the fish etc, look etc).
After 3 days, the BGA will be dead.
If you keep the tank clean, and the filter clean, do routine maintenance, add KNO3 etc routinely, BGA will never come back.
For some curiously odd reason, I never seen to get BGA, but then again my NO3's are always high and when they bottom out for longer time frames, I do not clean my filter, neglect my tank, do not focus on the plant's needs, I will get algae.
However, put another way, BGA does not appear in anyone's planted tanks due to a lack of pills or EM does it? So there's some other reason for it appearing in your tank, and it's related to plant health/growth.
So focus on growing plants(which is the original goal of most planted aquarist), treat the cause, not the symptom.
You will never really get better and be able to really help anyone grow plants better without focusing on the plants, sort of self evident but folks get side tracked nonetheless with their frustration with various algae species.
Well, then you come to an alga that cannot be treated with pills, then what do you do? This is about the only one that can be pill treated, but there are other cheaper ways, but neither is useful over time unless you focus on the cause.
The benefit of this approach is that it helps to grow the plants better, which is far better than any quick fix.
Regards,
Tom Barr