How to Kill Algae at a Carwash
- 1). Fill the washing mechanisms with phosphate-free detergents and cleansers. Empty all waste water down sinks that drain to safety-certified septic and leaching systems.
- 2). Fill a spray bottle with eight-parts water and two-parts bleach. Spray the algae to kill the existing growth. Spray only after hours and -- when the car wash gates are closed -- to prevent animals from getting into the bleach water. Scrape the dead algae off the ground or buildings.
- 3). Position fans or heat guns next to wet, algal-growth locations. Dry the algae and scrape it off the ground or buildings when dry. Rinse the surface with bleach water.
- 4). Check weekly to see if new algal growth is taking place. Spray new growth with the bleach solution, and wipe away before it develops into large patches.
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