I'm actually pretty good with plants! And, yes, I'm guilty of the "but I will succeed where others have failed!" thought process. No hurting the fish and snails, though. Not worth it.
I use 3% (the kind you get at the pharmacy) solution of hydrogen peroxide, which is not too harsh for plants. I use it on the roots of new plants pretty regularly, because I usually buy my plants on clearance at the end of the season, after they've collected everything gross they've encountered. For plants in dirt, though,i I usually add back a beneficial fungus. Not in the aquarium!
I had wanted to do some Harlequin rasboras. Hmmm