sidewalk stains

[Herkie Walls]

I have orange/red stains on my sidewalk from fertilizer. I tried to remove them with a pressure washer but it did not work. Any suggestions?

 

[bevo_daddy]

They are rust stains. See if you can find some concrete rust remover

 

[baboso]

Might also try muratic acid.

 

[Herkie Walls]

would lowe's carry concrete rust remover?

 

[baboso]

Yeah. The muratic acid also. Look in the paint department around the concrete paints/stains.

 

[Doughbroz]

There is a powder product called Iron Out that has worked for me in the past. And if you go the muriatic acid route, dilute it well. Straight muriatic acid will burn the hair out of your nose, as well as pitting the concrete.

 

[gbar1]

I would also recommend Super Iron Out (SIO) based on my own experience. You might want to clean the sidewalk with a pressure washer beforehand to get the dirt off of the sidewalk.

You can get SIO at Lowe's and similiar stores for around 11 bucks a bottle. It's a powder you mix with water. I found that if you mix 3 cups with 2 gallons of warm water (in well ventillated area) that works about the best without creating areas on the sidewalk that are much lighter than the rest of your already cleaned sidewalk. You basically apply it, let it sit until a yellow residue forms (about 15 min), and then you can hose that away with a normal water hose. You may have to repeat the process.

You can apply the product powder directly to a moistened sidewalk to remove very stubborn stains, but you will probably wind up with an area that is much lighter than the rest of the sidewalk if you do that, and you will use more of the product that way. It works best on moderate days (mid 70s range in farenheight) and in sunlight.

Finally, when you are done, if you have a pressure washer, you can go over the sidewalk again to even out any areas that are lighter if you have applied the powder directly or many repeated times.

Many concrete people will recommend Oxalic acid (wook bleach), but while that works very well, it is a more toxic and more costly product and will definitely lead to lighter areas on your sidewalk if not applied very evenly.

Under no circumstances should you use muratic or hydrocloric acid because these products will etch your concrete.