Good luck fighting it. It is hard to get rid of.
I still have a little of it, but I am at a much better place now, with relatively little of it left, and declining. Yeah!
I found the approach that worked best for me is a combination of sustained (read, weeks to months) mechanical and chemical attack on the BBA:
- Mechanical - physical (hand removal) of as much as possible, particularly new tufts on surfaces), then further vacuuming. Chemical by itself does not seem to do it. From driftwood, fingernail removal is best. From plants (depending on species), cutting off affected leaves/stems.
- Chemical - sprayed peroxide (full strength) onto surfaces. At every weekly water change, I begin with physical removal, then drain the tank as far as planned (usually 70% or more, while vacuuming loosened BBA), then spray surfaces (plumbing, heaters, driftwood, rocks, plants), followed by a few minutes wait time for the peroxide to act upon colonies, then refill tank. Over time, following the spraying (couple of days) existing colonies become reddish, then grayish, then die and fall off. Very important - when colonies are chemically affected (reddish, grayish), mechanical removal is easier and most effective. Thus, the chemical attack of one week is the edge one should bank on for next week's mechanical attack.
One more thing, if individual gravel pieces or sand are colonized, best is to replace substratum. For large (and desirable) rocks, take out, dip in peroxide (or clorox), then scrub with Scotch Bright pads, rinse, and reintroduce into tank. Do not spray Clorox onto aquarium.
Again, I still have some BBA and continue to fight it, but I have been able to save my planted tanks (for the most part).
Good luck!