Duck weed problem in pond

[saltwater cowboy]

Have a small trout pond (1500 sq ft) at my acreage. Last couple years had a duckweed problem but this year it's gone crazy. Every few days it almost covers the pond. I made a skimmer to remove the majority but it keeps coming back.
Any ideas ?
I aerate but it may not be deep enough. Pond is around 13 feet deep my aerator only works to about 8

[walking buffalo]

From personal observation with placing duckweed in water features as a start-up water conditioner.

Hard rain kills duckweed. Rain will bruise/damage the leaves, killing it in a few days.
Waves do the same thing, beating the leaves against the shoreline kill it.
Well, most of it, the few survivors will continue to reproduce.

Having some duckweed would be good for the water and fish, too much could be a problem.

So, one option to manage the plant in a small pond with trout is to hook up a pump to a large sprinkler.

[Wood1]

Excessive duck weed is usually a sign of high nutrient loading. Some causes could be runoff from pastures or fertilized fields. If you are feeding pellets, consider looking at the volume and duration times. Reduce or discontinue feed in winter as well. Other than manual removal or chemical spraying, your best bet is to control nutrients. Also review your stocking rates and maybe reduce your population.

Aeration can help and if you are using a diffuser(s) it should be at the bottom. Aeration does not dissolve air in to the water but lifts it to the surface where it interacts with the air. Bottom aeration will help in reducing excessive nutrients so maybe look at your system size/style and adjust as required.

Good news is you won’t see your duck weed this fall when water temps drop.....bad news is it just sinks and will be back next summer.

Hope this helps, it is difficult to control once it is established.

[schleprock]

Aerate 24 hours a day with your diffuser on the bottom of the deepest part of your pond and use a nutrient eating product that you can buy from ackenberry or smoky trout farms. Duckweed feeds on nitrates, nitrites and phosphorus but if you get rid of it’s good source you can beat it. You have a fairly small pond so it shouldn’t be that expensive to fix. The bad thing about the duckweed plant is that it reproduces like crazy and when the plant dies, it’s spores can sink to the bottom of your pond and will be back next year. Hope this helps.

[curtis_rak]

I’ve had the same issue for about 3 years now on a small-ish acreage pond basically the same size as yours. The problem with my pond is that it collects runoff from 2 slopes near the pond and being in a subdivision you have no control over what kinds of nutrients might be in the runoff (fertilizer etc). I’ve had the pond aerated since I’ve lived here for about 7 years now.

Ackenberry and Smoky Trout farms all have their recipes to get rid of the duck weed but neither worked for me.

What works the best for me is manual removal (a homemade, telescoping weed rake) and Reward herbicide. Reward is safe for fish and wildlife and kills the duckweed fast. Of course these are both bandaid solutions to the root cause which is nutrients.

I have another pond at a different property that is only a year and a half old, it’s in the middle of the bush and only collects rainwater (little to no runoff). It’s solar aerated and deep with clay sides (no black dirt) and the water is clear and zero weeds.

How old is your pond? How deep etc?


Sent from my iPhone using Tapatalk

[saltwater cowboy]

The pond is about 14 years old and 113 ft at the deepest. There are only about 15-20 trout in there now but they are all probably 3 pounds plus.
My present aerator/diffuser does not have enough power to work from the bottom so it is suspended roughly 7-8 feet down. I may hook up an air compressor and try that .
The rain seems to have increased the duckweed issues.
spend about 2 hours every 4-5 days manually removing but that sucks !!It can almost cover the pond in that time.
I will look for the reward herbicide to try that as I don't want to kill the fish
I mostly feed them spring and fall. Summer they are eating bugs constantly.

[Supermag]

I have a problem with a guy like that at work too!

Oh! DUCK weed.

Nevermind