Can You Use Bleach or Chlorine in a Concrete Fountain?

Water features are favorite additions to home gardens, but dirt and algae mar the relaxing focal point with discolored water, stained surfaces and unpleasant odors. For ease and convenience, many well-meaning advisers recommend occasionally adding chlorine or bleach to a fountain to maintain its appearance, but this advice is not always the best solution. While effective at removing algae and other contaminants from the water, chlorine is often not the best water conditioning choice.

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Algae clouds the water and stains the surface of concrete fountains.

Benefits

Bleach and other chlorine products are common in most households, so they are convenient additives to quickly remedy an algae-covered fountain or clear the water in a discolored fountain. Just a small amount of chlorine is needed to clear the water. Emptying the fountain of water and scrubbing it with a diluted bleach solution effectively removes tough stains, and the chlorine evaporates quickly, allowing you to refill and replace the fountain in a just a few hours.

Disadvantages

Chlorine tablets and bleach corrode concrete and will void most fountain warranties. Chlorine also damages the pump that circulates the water and can alter the color of the fountain. Most types of chlorine additives evaporate quickly from the water, especially in small quantities. However, slow- releasing chlorine chemical compounds can harm any animals that drink from the fountain while the chemical is present and active.

Process

Add 1 to 2 tsp. of bleach to the water in the fountain's basin to clear cloudy or discolored water and to remove algae, but this action may damage and disrupt the operation of the fountain's pump. For severe algae and staining, turn off the pump and empty the water from the fountain. Dilute a cup of bleach in a gallon of water, and pour the mixture directly on the stain. Scrub the solution into the surface with a medium-bristled scrub brush until the stain is gone, and rinse with clean water.

Alternatives

Aquatic & Garden Decor, a water garden supply store with 20 years of experience, recommends using algaecides to safely remove algae from fountains. Many algaecides are available at pond and pool supply stores that are safe for both the fountain and any animals that may drink from the fountain. These products are as easy to use as bleach products, but they are safer and will not void any warranties.