Here’s my problem. A customer has a concrete split block retaining wall that had efflorescence, which I was tasked with removing. The efflorescence was a white, mineral looking buildup, and was removed with a few applications of F9 Calcium and Efflorescence remover and some scrubbing. It did a great job with the white stuff.
Some other areas of the wall had a somewhat greyish buildup, (see pic) that did not respond AT ALL to the F9. I tried over 6 times, with literally no effect. I figured it must be something else, and informed the customer that it didn’t appear to be efflorescence. She was fine with that, but her architect came over and said that indeed it is efflorescence. I am going back next week to try again, and I would appreciate any suggestions. I was thinking about trying muratic acid, but I have doubts if that will work if the F9 didn’t touch it. I have researched this extensively and it sounds like it may be calcified, but I am not very experienced on efflorescence cleaning so any advice or suggestions would be appreciated.
Sure Klean 101 Lime Solvent and/or 600 by Prosoco. Muriatic acid as a last resort. Since it is split face block, you can get away with attaching a sand blasting attachment on your wand tip and using some very fine DRY sand or media to help remove the buildup. The attachment can be found at Northern Tool and maybe Grainger or your pressure washer supply store.
Thank you! Unfortunately there is a Koi pond about 2 feet away and all of the landscape rock at the base of the wall is brand new, so the customer will not want sand from sandblasting everywhere.
Would a wire wheel on a drill work?
I have used wire wheels before successfully. Make sure it’s stainless steel or just flood afterwards so no rust stains afterwards.
Thank you.
I’d try some nmd80- almost looks like a mortar smear.
I’ll try that as well. I’m going back with every possible solution.
Thank you
