The lazy way to remove duckweed from a pond

Some people love duckweed, while those reading this article no doubt hate it. There are a number of ways to remove duckweed: Physical removal, Water agitation, Chemicals. But these methods are tedious, costly or harmful to the water, plus the duckweed will return the next time a water bird visits your pond.

The best way I’ve found to remove duckweed from a pond is adding goldfish. Goldfish love feeding on duckweed and once eliminated will keep any future infestations away. But keep reading for a few other helpful suggestions.

Best of all you don’t need to do anything except buy some cute colourful fish! Goldfish are a really hardy fish and widely available on every continent except Antartica! But if you have a pond in Antartica i suspect duckweed the least of your worries.

Goldfish are usually cheap especially comets, which i find best for duckweed control. You can buy Amazon! Click for price. Delivered to your door!! Too easy.

Below is a video of me purposely adding duckweed to a pond with goldfish just to show how quickly they will demolish it.

Proven ways to eliminate or remove duckweed

  • Goldfish. As mentioned above this is easily the laziest way to eliminate your duckweed problem.
  • Adding a skimmer or intake bay.
  • Netting out. Effective when coupled with the goldfish method in small ponds.
  • Vacuuming. Below is a video showing how a cheap shop vac (wet/dry) can be very effective in controlling a duckweed problem.
  • Improving filtration and adding other non-invasive aquatic plants.
  • Chemicals. Last resort!

So as i mentioned Goldfish are a great way to remove an infestation of duckweed. When coupled with some of these other proven strategies you’ll quickly have that pesky duckweed problem under control.

Pond skimmers and intake bays are very effective at pulling floating materials into one convenient location where the can be collected and removed. They can easily be retrofitted to an existing pond.

If your pond is nice and small and installing a skimmer or intake bay doesn’t make financial sense purchase a cheap $15 pool net on eBay and manually remove the bulk of the duckweed. Then add a couple of goldfish and watch your duckweed issues disappear.

Even quicker than a net if you own a shop vac ( everyone should they are pretty cheap!) skim it of the surface in a minute or two.

Duckweed thrives in ponds with high nutrients. The duckweed is actually very effective at filtering these nutrients, and thats why some of us actually don’t mind incorporating it in certain tanks and ponds.

With that said if you can improve the filtration on your pond and prevent some of the nutrients being present in the water you’ll have a chance at slowing the growth of the duckweed. With the reduced growth you have a much better chance at full eradication.

Plants are natures natural filters, adding more plants that are non-invasive and you enjoy is a perfect way to also help reduce nutrient levels in a pond. In all my ponds i utilise bog filtration (click the link to read more). This couples biological (good bacterias), chemical (removal or nutrients) and physical (trapping solid particles).

I highly recommend you incorporate bog filtration in all your own ponds. If you subscribe to this blog you’ll get to see all my diy projects, how i keep pond water filtered naturally, and crystal clear all year.

Chemicals are a last resort and not something i have any experience with. All the above methods have been highly effective for me in my ponds.

If your problem is larger and requires chemicals I’m sure some ads will appear in this post. Check them out if necessary but please do your research before putting them into your pond.

Thanks for reading!


G'day, I'm Kev. My pond and water garden started with simple aquariums. I have created many ponds and water gardens around our home: Fish ponds, Aquaponic systems, grey-water wetlands and bog filters. My favourite topic is water filtration.

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