How to Get Stained Algae Out of a Cement Pool

High levels of algae in a pool cause real problems, in addition to making the water cloudy and unattractive to swim in. If the algae population grows uncontrolled, it adheres to the sides of the pool which results in an unsightly black, gray or sometimes slightly reddish stain. If you have a cement-sided pool with algae stains, the good news is that some vigorous scrubbing will return it to a stain-free condition.

Pool vacuum with brush attachment
Pumice stone

Instructions

- 1
  Turn your pool filter on so that it runs continuously. This is necessary to remove the algae from the pool water as you dislodge it from the cement portions.
- 2
  Examine the pool sides to locate one of the algae stains, which most often occurs at the water level. Walk to the area of the pool where the stain is and kneel or sit down on the side. If desired, you can also remove the algae stain while in the pool.
- 3
  Attach a brush attachment to your pool vacuum and turn the vacuum on. Place the brush over the algae stain and move it in circular motions to dislodge most of the surface staining. Repeat the process around the remainder of the pool.
- 4
  Move back to any severely stained areas that are still visible. Place a pumice stone directly over the algae stain and push down with gentle pressure. Move the pumice stone in circular motions just as you did with the brush. Continue until the stain is completely removed.
- 5
  Scrub all remaining stained areas of the cement pool with the pumice stone in the same manner until all of the algae stains are removed.
- 6
  Leave your pool filter on for at least 24 hours to remove any of the algae that floated off into the pool water.

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