Key takeaways for pond aeration

  • Use aeration to precipitate phosphorus out of the water.
  • Eliminate stagnant water. Duckweeds and water hyacinth prefer still waters.
  • Increase oxygen – floating biomass mats cause oxygen depletion and fish kills.

General takeaways for managing all aquatic weeds:

  • It is important to minimize nutrient inputs.
  • Integration of multiple strategies in your pond management plan will yield the best long-term return on investment.
  • Mechanical harvesting removes the nutrients contained in algal mats, thereby reducing overall nutrient load in the pond. Mechanical techniques may splinter stems and cause some plants to spread.
  • Dye controls algae by reducing the sunlight that penetrates the water and reducing photosynthetic capacity. It works only before the algal mat has formed. Dye concentrations must be maintained to be effective but reduce the beneficial phytoplankton needed for fish.
  • Physical controls like drawdowns, dredging, and sediment removal may be required to control some problem plants.
  • Using copper as an algaecide can be detrimental to aquatic life.
  • Triploid grass carp have been used to control hydrilla, pondweeds, and naiads but are not useful on duckweed and watermeal once the fish are larger. Grass carp will not eat algae, do no prefer milfoil, and won’t feed on floating vegetation. Not all states permit the use of grass carp.