How to Kill Brown Algae in a Pool
- 1). Test the pool's using a pool testing kit. Add chemicals as necessary to adjust the pool's pH level to between 7.0 and 7.2, the alkalinity level to between 85 and 100, and the water hardness to between 150 and 250 parts per million.
- 2). Add the normal amount of chlorine to your pool. Follow the application directions on the product labeling.
- 3). Clean the pool's filtration system once the chemical levels are balanced. Adjust the settings to circulate the water constantly until the algae is removed. Backwash the filter twice per day.
- 4). Scrub the sides and bottom of the pool vigorously using a long-handle pool brush. Remove as much algae as possible, especially over the drains and valves in the pool. Collect the loosened algae using a pool leaf rake afterward.
- 5). Shock the pool to weaken the algae. Raise the chlorine levels to at least 10 ppm, which should turn the pool cloudy. Add the chlorine in one application, rather than several gradual installments.
- 6). Add an algaecide formulated to kill yellow or mustard algae to the pool after the chlorine levels reduce to 5 ppm. Follow the directions on the labeling. Give the algaecide time to work before doing anything else.
- 7). Scrub the sides and bottom of the pool again to remove the remaining algae. Allow the remnants to settle to the bottom of the pool, then vacuum them up.
- 8). Continue circulating the water in the pool, scrubbing algae and backwashing the filter until all of the brown-colored algae is gone.
- 9). Clean or replace the filter twice per day until the algae problem is definitely gone for good. Resume swimming in the pool once chlorine levels reach 1 to 3 ppm.
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