Exterior limestone mold / mildew

[alazo1]

Folks,
Can you add bleach to Powermaxx?.

This is for exterior limestone that has black areas / mold.

thanks,
Albert

 

[sweendogg]

Albert, just some food for thought, but you may want to hit the mold with a little microbran space spray plus to actuelly kill the mold roots first, then follow up with a good bleaching agent to clean the mold. Otherwise bleaching usually only removes the surfaces spores and not always the roots, allowing it to return quickly.

Another possible option if you find that bleach/pressure isnt' removing it all the way.. you could always try a media blasting equipment.

On a not of the original question regarding adding bleach (sodium hypochlorite) to Powermax... why not use the bleach first, let dwell, rinse and then follow with powermax.. just a thought. household bleach is not a product that should be readily mixed with anything. And while I don't think there would be a reaction, its better to play it safe rather than chance the creation of the chlorine gas.

 

[alazo1]

David. Regarding the Microban, have you used anything else?. I don't have time to order the product but hitting it with something like it sounds like the right approach. I have some regular quat. Line one is the brand. I think I may still have some dd-12 on the truck as well.

thanks again,
Albert

 

[sweendogg]

The Quat may do the trick as well. I just know that if you don't kill the roots, the mold makes a quick return. Much like a weed will if you don't pull the root. It should say on the quat bottle if it will kill mold, and it should have an epa registration number as well.

 

[sweendogg]

Line One eh? You sure its Line one?

http://www.lineonelabsusa.com/index.php

 

[alazo1]

It's by Knapp manufacturing Line one NQR Non-rinse quat. I can't seem to find a website. Among other things it's a Mildewstat...whatever that means. It does have the EPA # on the bottom of the container.

thanks,
Albert

 

[Larry Cobb]

Albert;

Knapp Mfg. has some good products.

They are the old Steam Services in Calif.

Now on to the bleach question. PowerMax has an oxygen bleach, but I would add some more oxygen bleach for mildew.

It is a stubborn stain to bleach out completely.

The PowerMax has an actual enzyme that is compatible with the oxygen bleach.

Chlorine bleach would probably stop the enzyme, so I would not mix it with the PowerMax.

I would prespray a strong mix (8oz/gal.) on the mildew and let it dwell for a while.

Then pressure-blast the areas.

Larry

 

[alazo1]

but I would add some more oxygen bleach for mildew.

Larry, are you saying to add more Powermaxx that has oxygen bleach?. I also have your powdered and liquid peroxide.

thanks,
Albert

 

[Larry Cobb]

Albert;

Since you have our Powder Brightener ...,

I would form a paste and put it directly on the mildew .

Let it dwell 15 min. and then prespray the PowerMax.

Let dwell 10 min. and pressure blast with an (05xx) Spraying Systems washjet.

Larry

 

[Jack Zipper Zerkie]

Try using swimming pool chlorine, it.s twice the strength as house bleach, Chlorine is cheap compared to other items. Iv,e been pressure cleaning for the past 26 yrs and find that the right chemical will do a much better job than very high pressure,and have fewer problems. Two things dwell time and lots of rinising is the key for good results. jz.