The time has come again, the good weather is back and you're ready to sit outside and enjoy the fresh air. The only problem though, those paths, concrete, and driveway still look as black as they did last year. This black is most likely an algae just like that ugly green moss/aglae and needs to be removed to bring back that fresh look your property once had, when you first laid those hard surfaces. Sure, you can use a water blaster but this shaves years off the life of concrete and other hard surfaces.
Heres a quick guide on how to clean your paths, concrete, driveways and other hard surfaces without using pressure.
Algae grow on almost any surface and once it has developed over a long period of time, it can be incredibly difficult to remove. ‘Gloeocapsa magma’ is a common ‘black algae’ that grows on concrete and other hard surface and is tough! To remove this algae without pressure there are two main base chemicals to look for that will allow you to quickly clean your path, driveway or concrete and keep it clean all year round.
Sodium Hypochlorite: ‘Sodium Hypochloride’ is used in most ‘fast acting’ algicides and is effect at killing algae/ moss instantly. However, does not provide long-lasting prevention.
Benzalkonium Chloride: ‘Benzalkonium Chloride’ (benzyl alkyl) is used in most ‘control’ algicides that work over a long period of time and help keep algae and moss away. This product does not work instantly and can take months to completely killed algae and moss.
Safety Equipment should always be worn when handling chemicals including gloves, goggles, respirator and protective clothing.
Clear the target area from any leaves, sticks, dirt and anything that will get in the way from an even coating.
Apply an even coating of a 2-3% Sodium Hypochlorite based product to the target area. Make sure the target area is drybeforehandd.
Sodium Hypochlorite can be harmful to flowers and plants if allowed to come in contact so if you have any precious plants near the area you are treating, you may want to cover them up.
It should take around 15-20 minutes to kill the black algae but depending on how severe the algae is, you may want to apply addition coatings to completely kill the algae.
Apply the Benzalkonium Chloride based product to the target area to prevent regrowth.
After you are satisfied with the quick results you have just achieved, you will need to begin the process of preventing the algae/moss from regrowing in the future by applying a ‘Benzalkonium Chloride’ based product. This will act over a long period to stop that black/green moss and algae from regrowing.
Once the algae has been killed from the sodium hyper chlorite you will only need to use a Benzalkonium Chloride based product from there on to control the algae and other organic growths.
Depending on the area you live in will determine how often you should retreat the target are. If you apply every 3-6 months, you should see effective results.
If you have big pot plants sitting around and don’t want to move them very far just shift them to the side a bit and spray underneath them, then move them back. The chemicals will still work under the pot plant.