What Naturally Kills Algae in Pools?

Keeping your swimming pool sparkling clean involves more than just skimming off leaves and debris. Algae blooms can be a common problem for pool owners, and tackling them naturally is a top priority for those who prefer not to use harsh chemical algaecides.

In this article, we’ll explore the most effective, natural methods to eliminate pool algae and keep your water pristine all season long.

1. Understanding Pool Algae

Before we delve into how to naturally kill algae, it’s important to understand what we’re dealing with. Algae are microscopic aquatic plants that can cause your pool to turn green, yellow (mustard algae), or even black. When left unchecked, algae makes surfaces dangerously slippery, clogs your filtration system, and provides an ideal breeding ground for harmful bacteria.

2. Preventing Algae Growth

Prevention is always better than a cure, and this holds especially true for pool care. Here are a few preventative measures to stop blooms before they start:

• Maintain Proper Pool Circulation: Stagnant water is a breeding ground for spores. Ensure your pool pump and filter system run effectively to keep water moving, making it incredibly difficult for algae to take hold.
• Regularly Clean Your Pool: Brush and vacuum your pool weekly to remove any lurking spores. Pay close attention to corners, stairs, and shaded areas where algae typically starts growing.
• Test and Balance Your Water: Regularly test your pool water. Incorrect pH, alkalinity, or sanitizer levels create the perfect environment for algae to thrive.

3. Natural Methods to Eliminate Algae

If, despite your preventative efforts, your pool has turned green, don’t panic. Here are some natural methods to combat an algae outbreak:

• Deprive It of Sunlight (Pool Covers): Because algae is a plant, it requires sunlight to photosynthesize and grow. Utilizing a dark, opaque pool cover for a few days blocks UV rays and essentially starves the algae, making it much easier to clean up.
• Baking Soda & Borax: Baking soda helps maintain the correct alkalinity in your pool water, stabilizing your pH so your natural sanitizers can work efficiently. Borax (a natural mineral) can also be added to the water; it acts as a gentle, natural algaecide by interfering with the algae’s cellular development.
• Saltwater Systems: Converting to a saltwater pool is a highly effective way to manage algae naturally. The salt cell continuously produces a natural, steady stream of pure chlorine that prevents spores from blooming without the harsh chemical byproducts of standard liquid chlorine.
• Diatomaceous Earth (DE) Filters: DE filters are phenomenal at capturing microscopic algae spores. DE powder is made from the fossilized remains of diatoms (a type of hard-shelled microalgae), providing all-natural, microscopic water filtration.
• Elbow Grease (Brushing): The most natural method of all! Algae forms a protective slime layer over itself. Vigorously brushing the walls and floor breaks this barrier, allowing your filtration system to sweep the spores away.

4. The Aftermath: Treating Your Pool Post-Algae

Once you’ve successfully treated the water, there’s still work to be done. Spores are notoriously hardy and can easily return if you don’t follow up with proper maintenance.

• Deep Clean Your Pool: Thoroughly vacuum the dead algae directly to waste (bypassing your filter so it doesn’t get clogged).
• Shock Your Pool: Even after treating the algae, a shock treatment ensures that all remaining invisible spores are eliminated. Choose a non-chlorine oxidizing shock for a more natural approach.
• Clean Your Filter: Your pool filter has likely collected a massive amount of dead organic material during the treatment process. Backwash or manually clean the filter to ensure it operates at maximum efficiency.
• Monitor Pool Chemistry: Keep a close eye on your chemical levels post-outbreak. Test your water daily for the first week to ensure it remains perfectly balanced.