i hate to inform you that this aglae is the FW version of herpes, once you've got, you've got it for the life (hope that's not offensive to anyone, except the algae). a single cell of this is all it takes when the conditions are right. i have been fighting it for years, all you can hope for is stasis. Bleaching plants and ornaments will very effectively remove it from surfaces but it's floating in the water column on a microscopic level. i have a 40gal with 4 SAE's, yes they'd occasional graze on it but not like my 9 yr old daughter at the movies with a bag of popcorn, more like a deer i the forrest nibbling the tender leaf shoots. now with that said, I've never tried mollys but I hear they are the goat of the aquarium and maybe they would take it down to the surface, SAE's definitely won't.
i recommend a good aquavacing and water change at the same time as the 1:19 bleach bath, knock it's population down . . . controlling it's nutrients and you control it . . kinda.
tolerance and acceptance, celebrate diversity . . .
but bleach that BBA to :devil:!!!
Good luck