How do I get rid of duckweed on an aeration basin?
asked 18 August 2017 asked by DBeaux (360 points)
Is the duckweed in the aeration basin or on the clarifier? If it's the clarifier and you can safely access it, then you can gather up the duckweed using a net, a skimmer, or another floating device; for example a PVC pipe and then pump it out with a vacuum truck.
Hi, To add to Tonino's answer, one interesting option for a basin is to drive the weeds towards a central point using a floating dam or weir (like the kind found in ports/harbors to prevent pollution from seeping in). That way the duckweed is collected gradually, and the bonus is that this type of system allows you to accumulate it to a pretty significant depth.
And after that, you could invert an impeller pump (volute toward the surface) and send the duckweed wherever you want. Low speed for a few minutes every 1/4 of an hour. Otherwise, in a lagoon, certain fish like grass carp and koi feast happily on duckweed (haven't tried it on a clarifier though).
Dolu, the inverted volute idea is genius. If not, for a lagoon you could check out certain species of duck—the best part is that a well fed duck has beautiful breasts and legs...delicious dining :)
Hi, Removing duckweed implies that it actually poses a problem. If it doesn’t, or as they say, if it ain't broke, why fix it? One other idea, based on some research I did is to investigate upstream to see what might be feeding your aeration basin. I know of one plant whose rainwater reservoir was the culprit. The treatment was done at the source at no cost to the plant.