cream peroxide h202

hi guys just another question on h202.
my gf is a hairdresser and she has a couple bottles of cream peroxide

here is the stuff i have the 12% and 9%
http://www.coolblades.co.uk/re-oxide-cream-peroxide.html

basically can i use this stuff on my plants? why buy if its around your home!!

And you would want to use this stuff . . . why?

root rot and algea