Mystery Stuff on Rock Home

[dcoronado]

Hello all,

I am not sure what this black stuff is on this rock house. I thought it was mold but applied bleach 50/50 on it several times. Then hit it with the hot water, re-applied bleach and hit it again. Needless to say I have hit it approx.
10-12 times with what ended up being straight bleach and it still has not come off.

I also tried Zep commercial all in one cleaner...did not do much either.

I do have to say that this one rock was totally covered with black..approx 85% at least and now it is to this (see pictures). I want to get it all off but am not sure what else I should try. Thought about acid but since I am new do not want to really mess with this stuff yet.

Well unable to attach picture because states file to large even though at lowest quality...and file is still twice as big as what it allows to be attached???

Thanks,

Daniel

 

[PressurePros]

You are best off to use a specialty stone/masonry cleaner. I use products from Eaco Chem with great success.

 

[Revive]

Daniel

E-mail a picture to Larry at Diedrich Technologies. He's their tech support guy. Or as Ken says, Eaco Chem, or even call Prosoco. That's why they have technical assistance department's.