How to Keep a Pond Free of Algae

Prevention is of the utmost importance when it comes to keeping a pond free of algae. The correct balance of sunlight, aquatic plants, the appropriate filters and maintenance creates a water garden ecosystem free of excessive algae growth and mess.

Things You'll Need

  • Aquatic plants
  • UV pond filter
  • Pond skimmer net
  • Scrub brushes
  • Pond vacuum
  • Anti-algae chemical solutions
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Instructions

    • 1

      Position the pond in your yard in a place that gets partial sun throughout the day. Continuous sun will increase the rate at which algae grows in the water garden. Limiting sunlight to just that required by the aquatic plants is ideal.

    • 2

      Plant enough aquatic plants to cover at least half of the surface of the pond water. Water lilies and floating plants like water hyacinth offer great coverage, as does the tiny duckweed plant. Also plant plenty of underwater oxygenating plants like anacharis. They will use up nutrients in the water so algae will not have enough to flourish.

    • 3

      Attach a UV pond filter to your existing filter, or purchase a new one. UV lights in the filters kill algae cells when they pass through the filter. The dead algae cells are caught in the filter or pass through to float in the pond, unable to reproduce.

    • 4

      Remove pond algae manually with a long-handled skimmer net or dip nets. Hair algae can be removed by twirling a stick around it and pulling it out in a glob. Scrub any exposed rocks and water garden fixtures such as waterfalls and fountains with a stiff brush to remove algae growth and vacuum up the detritus.

    • 5

      Use commercially prepared algaecide chemicals when other methods used to keep a pond free of algae fail. Follow manufacturer's directions to add the minimum quantity to the pond. Use a net or skimmer to remove all algae as it dies.