Short Answer:
Control duckweed with surface movement, nutrient reduction, and removal.

Detailed Answer:
Duckweed thrives in still, nutrient-rich water.

Control methods:

• Aeration (creates surface disturbance)
• Skimming/removal
• Nutrient control (especially phosphorus) with pond bacteria and/or binders
• Herbicides (if needed)

Key insight:
Duckweed is often a symptom of excess nutrients.