I'm starting to think this is foolishness.
Every time a tenant moves out of one of the apartments in my building, I remove the mildew that is growing on the silicone caulk in the bathroom. I do that using bleach.
And, once that mildew has been cleaned off, it takes just as long to come back and become established as it did when the caulk was new.
That tells me that when the mildew comes back, it's new mildew growing on the silicone caulk, not dead mildew that has come back to life.
So, could someone please explain to me why, if after cleaning the mildew off the side of the vanity, and seeing that it comes back in 3 or 4 years, why Homefish would replace the vanity rather than clean it off a second time to get another 3 or 4 years out of it?
And, why would he replace the vanity when, in all liklihood the new vanity would get spattered with soap scum and would have mildew growing on it too within a few years?
Finally, I have cleaned mildew out of discoloured cement based grout MANY MANY TIMES over the past 20 years. And I've done that with bleach. So, this suggestion that bleach loses it's effectiveness as soon as it enters a porous surface is bogus. Cement based grout is porous. Also, woodworkers will often try to remove stain from wood by bleaching it out. They mix swimming pool chlorine crystals in bleach until the crystals don't dissolve anymore and use that concentrated solution to try to bleach a wood stain out of wood. Often, they won't bother with the swimming pool chlorination crystals and just use bleach straight out of the jug. Wood is porous too. And, of course, if bleach lost it's effectiveness when it entered a porous fabric, wouldn't that be common knowledge amongst housewives that you need more bleach to remove a stain from a thick cotton fabric, like blue jeans, than from a thin one like a t-shirt?
Ya gotta remember, this is ordinary mildew. The kind that grows on grout lines. Millions of people have it all over their bathroom walls, and have for years.