How to Decolorize Ponds With Fish

Whenever fish are present they make biological waste that can foul water. Bacteria and protists can "bloom" under such conditions, multiplying until they cloud the water. Fortunately, there are tiny crustaceans that can devour the microscopic organisms that are making the water a cloudy color. At the same time, a pond keeper must identify the root cause of the cloudiness to prevent further blooms. With a little effort, a cloudy pond may be cleared.

Things You'll Need

  • Test kits
  • Daphnia culture
  • Pond filter, or fresh filter cartridges or inserts
  • Bucket
Show More

Instructions

    • 1

      Test the pond water with an ammonia, nitrate and pH kit. Ammonia levels should be at zero PPM, and nitrate should be at or near zero. The pH should be between 6.8 and 7.5. If the pH is out of that range, consider using a commercially available buffer to correct it. If ammonia or nitrate is the problem, continue to step 2.

    • 2

      Add a Daphnia culture to the water. Daphnia are tiny crustaceans that will feed on the algae or bacteria, and provide a snack for fish. They can usually clear a pond in a few days to a few weeks.

    • 3

      Check filters, or add one if you do not have one. A blocked filter can cause a deterioration in water quality. This can allow algae to thrive. Replace cartridges and rinse or replace inserts depending on the brand of filter.

    • 4

      Perform a partial water change of the pond. This will help remove some of the ammonia, nitrate, or other organic compounds the algae is feeding on.

    • 5

      Control feeding. Overfeeding is a major cause of algae blooms, as is overcrowding your tank. Consider splitting fish into other ponds or tanks if they are overcrowded.