How to Get Rid of White Floating Stuff on Top of Pool Water

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Eliminate white mold and get back to enjoying your pool.

White matter floating on the surface of your pool may seem a little repulsive, but the possible causes are fairly easy to understand, and the solutions equally simple. This white matter is likely the result of algae or mold, and it's important to determine which you are dealing with in order to correct the problem.


Algae is a very simple aquatic organism that generates its growth through photosynthesis. It generally arrives in you pool on the wind or rain, or sometimes by contaminated swimming suits are pool cleaning equipment. It is not a dangerous organism in any way, but it can make your pool murky and unpleasant to swim in. Algae turns white when it dies, so it is possible that the white matter you see is simply dead algae. This is especially likely if you've recently done battle with algae through chemical treatment of the pool. Just let the debris settle to the bottom of the pool, where you can vacuum it away as part of your normal maintenance routine.

But if you haven't been at war with algae, it's far more likely that the masses in your pool are actually living white mold, not dead algae. If so, an algae treatment won't solve the problem. Unfortunately, pool owners looking for help are often advised to treat algae rather than mold. Don't make the same mistake. Treat your pool water for white mold and then add an algaecide as a precaution.


Here's how to address mold problems in your pool.

Step 1: Use a Pool Net

Remove as much of the white mold as you can with your pool net. When you remove it, shake it out into a trash bag. Don't put it onto your lawn or on the ground around your pool, because some molds can infect lawn grasses.

Step 2: Scrub the Pool

Scrub your pool walls with a heavy-duty scrub brush. Even if you can't see any mold there, scrub around the walls of the pool as thoroughly as you can. Pay special attention to shaded areas, such as behind pool ladders. Clean in and around your skimmer and return jets as well, and backwash your pool filter.



Clean any pool toys or floats, as well as the pool itself, to avoid re-contamination.

Step 3: Test pH Level

Check your pool's pH level and adjust it as necessary to obtain a pH level between 7.2 and 7.6. Mold is more likely to occur if pH levels stray away from optimal levels.

Step 4: Shock the Pool

Turn on the pool's filter and quadruple-shock the pool by adding four pounds of calcium hypochlorite for every 10,000 gallons of pool water. White mold is tough to kill, so don't skimp on the shock. Run the pool filter for 24 hours.

Step 5: Add Filter Cleaner

After 24 hours, add a filter cleaner to your pool. If algae is a concern, also add an algaecide at this time. Leave your pool filter running for three or four days. Brush and vacuum the pool every day during this time.



You may need to temporarily turn your pool filter off after adding filter cleaner. If so, simply turn it back on again as soon as you are allowed.

Turn your pool filter off when vacuuming so that any debris can settle to the bottom of the pool for easier removal. Remember to turn it back on immediately after vacuuming.

Step 6: Test the Water Chemistry

Test your pool water. It is safe to let swimmers in the pool again when the chlorine level drops back down to a reading of 1 to 3 ppm.

Step 7: Prevention

Prevent future white mold issues by maintaining a chlorine level of 3 ppm at all times. Brush and vacuum your pool twice a week to keep mold spores from taking hold.



Home is where the heart is, and Michelle frequently pens articles about ways to keep yours looking great and feeling cozy. Whether you want help organizing your closet, picking a paint color or finishing drywall, Michelle has you covered. If she's not puttering in the house, you'll find her in the garden playing in the dirt. Her garden articles provide tips and insight that anyone can use to turn a brown thumb green. You'll find her work on Modern Mom, The Nest and eHow as well as sprinkled throughout your other online home decor and improvement favorites.

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