Pond Boss Forums GENERAL QUESTIONS Help Duck Weed

Does anyone have a suggestion about removing duck weed manually?
Thanks...

See the "Prickly Rope" thread here.

Skinman make the rope,youll love it.The more zipties the better

Hey Skinman,

How large is your lake? How much is covered with duckweed?

The pond is 3 acres, depths from 3 ft to 10 ft, and about 7/8 of it was covered with duckweed. I was hoping the duckweed would die out after a few frost, but it hasn't.
I just bought a farm 2 1/2 years ago. Its a chicken farm, and I'm trying to build up a decent herd of cows on it also.
The pasture around the pond is a hayfield, and has been fertilized with chicken litter once a year. The previous owner built the pond in 1998 and stocked it with 500 Catfish, 100 LM Bass, 50 Bluegill, and 50 White Perch. He added carp throughout the years. Everytime I take the kids fishing on it, they catch the bluegill like crazy. I can't catch a catfish or bass for anything.
This past summer, we had a turnover. One day in early July, I found about 100 fish floating in the pond.
Between the turnover and the duckweed, I've decided to drain the pond this week. It has a 6 inch syphon drain system on it. I got it going the other day, and the water that was coming out at first looked and smelled like raw sewage. It cleared up after a half day of draining.
I going to start over and see what happens.... Maybe you guys can get me lined out!!!

Hello and welcome Skinman.

Draining the pond won't ensure the end of the duckweed. Once drained, the pond bottom would have to be either thoroughly frozen, baked in the sun, or treated with herbicide. It only takes a few surviving DW plantlets to start another infestation.

It's normal to have some foul-smelling sediment in older ponds, even without runoff from fertilized fields. Unless the water always stays very green with little visibility, the fertilized fields probably aren't harmful.

If you don't mind, I would like to know what kind of fish you find when the pond is emptied.

Good luck,

What about treating with Sonar AS? Too expensive maybe? At least it's simple and effective.

I finished draining the pond. The only fish that was left in the pond were bluegill and hybrid brim. There were ZERO catfish, bass, and white perch. I thought there would at least be some bass left with all of the brim in there to eat.

its time to start over!!!

I hate to be a stick in the mud but duckweed is beneficial three-fold. It is a good protein source for the fish and will prevent algae bloom by blocking direct sunlight which will likely kill off all your fish especially with the addition of cattle urine and it will take up excess nitrates. Cattle urinating in the pond likely caused ammonia spikes which killed off the larger fish requiring more oxygen and are more succeptable to nitrite levels than smaller fish. I could of course be way off but duckweed's real only negative is making it hard to fish. My neighbor's pond stays covered with duckweed all the warm months and has a healthy fish population...no cattle! Cow piss moss we call it, a scummy green STINKY moss like substance will deplete oxygen levels as quickly as a full algae bloom...

From TX A&M Aquaplant

Common duckweed is a very small light green free-floating, seed bearing plant. Duckweed has 1 to 3 leaves, or fronds, of 1/16 to 1/8 inch in length. A single root (or root-hair) protrudes from each frond. Duckweeds tend to grow in dense colonies in quiet water, undisturbed by wave action. Often more than one species of duckweed will be associated together in these colonies. Duckweeds can be aggressive invaders of ponds and are often found mixed in with mosquito fern or watermeal. If colonies cover the surface of the water, then oxygen depletions and fish kills can occur. These plants should be controlled before they cover the entire surface of the pond.

That is a nice version above.

There is plenty here on DW. DW is the bane of fish ponds. In addition to causing an O2 depletion by covering the surface it kills the plankton (light denial) and thus the base of the food chain. The fish die from starvation or O2 depletion - take your choice. DW is very hard to kill.

http://www.pondboss.com/forums/ubbthreads.php?ubb=showflat&Number=35630&fpart=1

http://www.pondboss.com/forums/ubbthreads.php?ubb=showflat&Main=3551&Number=35724#Post35724

http://www.pondboss.com/forums/ubbthread...=true#Post34840

Ok I stand corrected on the duckweed and learned something. Since Duckweed thrives in ponds with high levels of phosphorus and nitrogen, it would be safe to assume the surrounding pasture being fertilized with chicken manure and the resulting run-off from rainwater leaching is providing the pond with too many nutrients that make the duckweed flourish. If it is so hard to kill off completely it might be best to focus on a control and stock some fish that eat it and so create a balance. Crayfish love duckweed both dead and alive. One can actually watch them swim up to the top flipping their tail wildly and grabbing some on the way down. There are likely other fish that eat it as well like Talapia that might be stocked if the temperature is adequate.

ETA...Ah I see SkinMan is in LA. Going to be very hard to do away with it as mentioned in one of the other threads due to the birds carrying it in from all over the place. Talapia do well in Southern ponds if the water temperature does not go below 55. They'll get fat and happy on it

CharlieLittle those are astute observations. The one I have seen the least on (saw it while doing the prior post) was tilapia use. It should have been an obvious one for me but some how I missed it. I knew most plant eating fish would not eat DW but did not check on tilapia. That may be a very good option for those who can use them. You are correct that the best option if workable is to manage the nutrients. The rope seine works well but as DW can double in volume every 24 hrs it makes for some work keeping up with it.

I used to have alot of links to Talapia, crawfish and certain carp being raised on only DW but not any more. DW is a valuable addition to aquaponic systems as it is a high protein source feed. If a healthy balance can be obtained with it then all the better. There are chemical solutions but they are expensive and tricky.

I was always under the belief that DW was beneficial but I have always looked at it from an aquaculture point of view and not a pond owners.

Even tried to get it started in a 12ft diameter pool with crawfish but they ate it all so fast it didn't have a chance