Home Improvement--General/Stain on cinder block


I have cinder block walls in the basement of a townhouse I am planning to sell.  I rented  the townhouse for about 4 years previously to a tenant who neglected to tell me there was water coming through 2 windows that left stains on the cinder block.  I tried to clean the stains with a pressure washer, a wire brush and also ammonia, but there is no change.  I don't want to paint, it would be a dead giveaway that there was a problem.  The problem has been fixed by a drainage expert but the stain remains.  I am afraid to use bleach that it might change the color of the blocks.  Any suggestions as to what I might try?  Thank you, Clark.

You need an acidic cleaner for minerals.  I would try some Muriatic acid and a brush followed by a scrub rinse.  Or you could get some Dura Klean from www.concrete-floor-coatings.com which has some detergents and water softeners in it.  You will have to do the entire wall because the cleaner will lighten were ever it is used, and can make the texture a little rougher.  

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Harvey Chichester


Expansion joints, Concrete floor coatings, bubbles, craters, floor repair, industrial flooring, garage floor seals, building maintenance, and floor paint,


Harvey Chichester is a well published principal of Durall Industrial Flooring, a company with more than 40 years experience in developing special flow-coatings for industrial and residential floors. Automotive and shopping centers, breweries, food processing plants, manufacturing plants, airplane hangars, car washes, kennels, warehouses, printing plants, residential basements, pool decks, and condominiums are among some of the facilities in which he has installed floors. http://www.concrete-floor-coatings.com During that time, his team of chemists has produced continual improvements to over 500 products, including the acclaimed Dura Seal and Dura Poxy lines of epoxy floor coatings. He has managed installations in all 50 states, 5 Canadian provinces, and 7 countries.

Durall Industrial Flooring

Aricles appear in over 3500 locations on the web.

MBA Marketing, BSB Finance minor Management, BA Economics minor Sociology, 7 years working beside Bench chemists at Durall Industrial Flooring.

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Iowa Beef, Pillsbury, General Mills, Banta Printing, 3M, Control Data, UFE, Land O Lakes, Thousands of residential garages, warehouses, machine shops, and automotive centers

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