Always fill the watering can with water first and then add the acid. After you clear a space, pour the mixture from a watering can over a small, manageable area. After about three minutes, generously hose off the muriatic acid solution before it can start to damage your pavers.
Acids and acid-based cleaners can, and all-too-often do, cause devastating damage to the appearance of some types of paving. However, being wise after-the-fact is all too easy.
Unfortunately cleaning is not a one-size-fits-all process for pavers. For example, masons will use muriatic acid on clay brick to remove mortar. However, muriatic acid could do serious damage to a concrete paver.
Acid cleaning using hydrochloric acid (HCl) should normally only be used to remove mortar stains. Therefore, only pavers that have been wet-bedded may require acid cleaning. Generally, hydrochloric acid should not be used to treat any other stains or at any other time during the life of your clay product.
Cleaning effloresence and stains from pavers is easily done using an acid wash which requires only a broom, hydrochloric acid and water.
Any acid used incorrectly can damage the brick or cause unsightly staining and can be more difficult to repair. Cleaning vanadium stains with hydrochloric acid may turn the salts black and make them more difficult to remove.
Dry brushing with or without application of clean sharp sand. OR High pressure water jetting with or without detergent. OR Apply fungicides. Use ordinary bleach or calcium chloride followed by sodium hypochlorite dissolved in water (1kg in 5 litres) then scrub with stiff brush.
The safest cleanser is a mixture of warm water and a mild household cleaner, like dish detergent. Fill up a gallon sized bucket with water and add about 16oz of dish detergent. Mix the soap into the water thoroughly.
Over time, it can destroy concrete as the acid weakens its structure. This will cause scaling, pitting, peeling, and cracking. If the acid wash gets into the soil, it will evaporate on the surface but remain beneath the surface (just like it does with concrete).
To clean and etch concrete, mix one part muriatic acid to 10 parts water. Brush or spray the acid solution on the concrete, wait eight to 10 minutes, then neutralize the acid by spraying the surface with a mixture of one cup of ammonia in one gallon of water.
When cleaning with basic pH chemicals such as sodium hypochlorite, you remove dirt, mold, and algae from surfaces easily, but do not get the brightening effects acidic pH chemicals, such as muriatic acid, provide. Muriatic acid can provide that bright white look that new concrete often has.
The calcium carbonate creates the whitish haze on the surface of the concrete pavers. As the moisture evaporates off the surface of the pavers, the whitish haze becomes more pronounced. And as naturally as the efflorescence appeared, it will fade.
The acetic acid in vinegar is a little stronger than acid rain, so exposing your pavers to this substance can lead to bleaching, corrosion and the loss of protective sealant.
The phenomenon of efflorescence occurs when water soluble salts migrate to the surface of the paver with the help of water (i.e., condensation, rain). Once the mixture of water reaches the surface, it mixes with the carbon dioxide in the air and creates a white haze/film that covers the pavers.
Mild detergent and water. If your pavers aren't too dirty, this can be a quick and easy way to clean them without any fancy equipment. Mix some mild dish soap with water in a bucket to create suds, then use a brush or a sponge to scrub the surface of the pavers.
Dish Soap: A great way to clean patio pavers without removing any sand or decorative texture is by simply cleaning with a gentle soap or degreaser like Dawn. Add the dish soap to a container of water, then start lightly scrubbing the dirty spots with a rag, sponge or a stiff-bristled brush.
But firstly, let's recap what brick acid is. It's basically hydrogen chloride (HCl) dissolved in water. A liquid with a strong smell, it's miscible with water, hazardous and corrosive. It is also known as muriatic acid and hydrochloric acid.
I would scrub with water only @10hrs - 48 hrs. I wouldn't use muriatic/water until 3-4 weeks. Be sure to add acid to water, not water to acid. An 8:1 (water-acid) mix is a good place to start.
Hydrochloric acid for brick cleaning is available from hardware outlets. The wall MUST be thoroughly saturated, and remember, no matter how dirty the wall is NEVER use more than 1 part of hydrochloric acid to 10 parts of water. It helps to start by using 1 part acid to 15 parts water mixture.
Using a stiff broom, apply a 10: 1 solution of water and sodium hydrochloride (liquid pool chlorine) to the effected area. Scrub pavers well. Once all affected pavers have been covered and scrubbed, leave for approximately 20 minutes. Re saturate garden again and then hose any residue off pavers.
Although bleach is great at the whitening effect, you can use peroxide to achieve this. Hydrogen peroxide is an oxygenated bleach. It is safe for plants, so when you rinse this solution, it won't harm anything. It works together with the dish soap and baking soda to remove dirt and whiten dirty concrete.
First, for very mild cases of efflorescence, try a 50/50 mix of white vinegar and water. Using a scrub brush, spot treat and scrub affected areas with the vinegar mix. The acidity in the vinegar helps remove the efflorescence and calcium deposits by breaking down mineral crystals.