Black algae can be killed by chlorine such as bleach or if in a pool chlorine tablets can kill the black algae.
You can also use vinegar and baking soda to kill off black algae on concrete or patios or also use the bleach.
Black spots on patio is caused by algae as well as mildew, mold or even lichen growth that thrives in moist and shaded areas.
You can use bleach or bleach and detergent or even baking soda and vinegar to remove patio black spots.
Then spray the patio down with a pressure washer or garden hose after scrubbing the patio.
To clean a concrete patio without a pressure washer you can use some baking soda and vinegar or bleach and detergent.
Then use a scrub brush to scrub the concrete patio and then use a regular garden hose with a sprayer to clean the concrete patio.
Vinegar and baking soda or bleach or detergent are good for cleaning concrete patios.
The best thing to clean concrete is baking soda or vinegar or both baking soda and vinegar.
You can also use bleach and or detergent to clean concrete but they can kill off some plants.
You can clean a patio with bicarbonate of soda and also vinegar.
White vinegar will clean concrete and it will clean concrete even better when you also use some baking soda as well.
You can remove black algae from concrete by using some baking soda and vinegar.
Pour the baking soda over the black algae and then pour some vinegar onto the baking soda and let it sit for 10 minutes or so and then scrub the concrete with a brush or pressure washer to remove the black algae.
Black stains on concrete are caused by black algae that grows on many outdoor surfaces including concrete and can thrive when there's is moisture and sunlight.
Black mold can also cause black stains on concrete.
To remove black stains from concrete you can use some baking soda and vinegar or baking soda or vinegar.
Mix equal parts of vinegar and water together and then scrub the concrete with the mixture and then give the concrete a good rinse.
You can also use some baking soda along with the vinegar or use the baking soda by itself but using baking soda and vinegar will remove the black stains from concrete much faster and easier.
To get concrete whiter mix 1 cup of bleach with 1 cup of powdered laundry detergent, then add 15 cups of hot water.
Then pour the mixture of bleach and laundry detergent over the driveway's dirty areas, such as the parts that contain oil stains.
Next work the mixture of bleach and laundry detergent in using a bristle brush and scrub for approximately 20 minutes.
After that you can hose the concrete off or pressure wash the concrete.
Baking soda can be sprinkled on concrete stains including oil stains on concrete and after sitting for around 30 minutes and scrubbing the concrete it can help clean the oil stains and other stains from the concrete.
You can also add some vinegar to the baking soda on the concrete to help it clean the concrete better.
Straight bleach will not harm concrete as long as you wash the straight bleach off after around 30 minutes to an hour.
To clean concrete with bleach you can apply the straight bleach to the concrete surface and then wait up to 15 minutes to 30 minutes and then pressure wash or scrub the concrete and hose it down.
Bleach is commonly used to whiten concrete and is very effective at doing so if the initial stain is removed beforehand.
Bleaching stained concrete white prepares it for any additional coloring treatments that you may wish to apply in the future.
Concrete can be damaged by power washing if you're not careful.
While concrete is pretty tough and can stand up to rough conditions it's possible to damage concrete with pressure washing.
If you're not careful the pressure washer can cause etching in the concrete.
Because a pressure washer is 30-80 times stronger than your hose, it can cause damage if used improperly.
And if the concrete becomes etched during the pressure washing, you should stop before causing further damage and reduce the pressure.
Sealing your driveway after pressure washing will further protect it from the elements and any dirt and debris that stains the surface.
After the concrete has dried for at least 24 hours, you can effectively apply a concrete sealer.
A sealer helps prevent future stains and potential damage from products like ice salts.
In general you'll want to pressure wash your concrete at least once a year.
This lets you treat sunbaked dirt, grime buildup, and stubborn oil stains, making regular cleaning in between washes much more manageable.
Of course, you can always schedule extra pressure washing services as needed.
Some things you can spray on concrete before pressuring washing are.
Acidic Cleaners. Acidic cleaners are heavy-duty mixtures that remove stains, dirt, and contamination soluble in acidic solutions.
Alkaline Cleaners.
pH-Neutral Cleaners.
Bacterial Cleaners.
Any pressure washer capable of producing at least 1,500 pounds per square inch (psi) of pressure can clean concrete, but the work will go much faster if you choose a model producing 2,500 to 3,000 psi, like the gas-powered pressure washer.
Powerful pressure washers with too much PSI will damage concrete when power washing.
Most residential driveways require no more than 3000 to 3500 PSI for proper and thorough concrete washing.
Heavy-duty commercial pressure washers and other power washing equipment are too strong for the average residential driveway!