Pond Boss Forums AQUATIC VEGETATION Controlling unwanted plants What to do with dead/dying pond vegetation after treatment?

Captain is only good for algae not weeds. The pic you posted doesn't look like duckweed either. I'd stick to Weedtrine D or Reward if you are unsure of the plant. The dead biomass just goes to the bottom so try using microbes. Best thing to do is treat early with Reward or Fluridone to keep the plant mass down to a minimum and keep the pond dyed.