HELP!Botanist preferred answer please?

I have recently had an infestation of duckweed, the type that looks like clover and grows very rapidly. My pond is a wildlife habitat, i.e. several species of frogs and a few lizards/newts that visit occasionally, and the regular patrols of dragon flies some quite large with exotic markings and coloration. I do not want to use any chemical that will harm them, as I have built this haven in the middle of the Black Country over many years. My only other option is to drain the ponds and start again, which I do not want to do if at all possible, I have tadpoles still awaiting full adulthood, they would have to be sacrificed, which to me is not an option, but if I cant clear the weed then they will all perish anyway i.e. rock and a hard place choice. Any educated replies much appreciated.

HELP!Botanist preferred answer please?
You have three options here. First is a chemical application that really should be done by professionals. You could do it yourself with careful reading ahead of time. Not all chemicals are harmful to the pond's occupants. If the entire pond is overcome by the duckweed then you will have to treat 1/3 of the pond at a time. Interstate products puts out an aquatic weed eradicator. You dilute it per package directions and spray just the tops of the duckweed.


Secondly, you could use biological controls but it depends on how far the duckweed has overgrown your pond. Carp and tilapia eat duckweed. Certain waterfowl(ducks) eat it also but they can also reinnoculate your pond afterwards with duckweed on their feathers.


Lastly, you can mechanically remove it if the pond is not huge. Hand skimmers are used like mowing a lawn, row by row to get every bit. If you have a large pond there are mechanical skimmers available to remove weeds from the roots up. Good luck!
Reply:as already stated removal using net .you may already know but if not.you can buy quite large nets(triangular 4ft across)on very strong handles up to 9 ft long for about £10 ,you get them at angling shops,ask for carp net.hope this helps.
Reply:This is probably not the answer you want, but since I've had the same problem I'll tell you what I do. I skim the duckweed regularly. My pond is small, roughly 8X24 feet; periodically it get covered with duck weed, I use a wide net to skim it out. After skimming, dump what you have skimmed into a deep bucket full of water. Then stir the mass gently to allow any tadpoles, dragon fly larvae and so on a chance to escape from the mass of duckweed before you dump it. Duckweed grows very fast in hot weather, and you'll have to do this weekly probably. It's a real bother.


There are herbivorous fish such as grass carp which might help with this problem in big ponds, but I have not yet discovered a small, winter hardy herbivorous fish which will control duckweed. Let me know if you have!
Reply:there is no chemical that wll not actually harm the animals and kill the weed. your best bet is to fish it out daily with a net untill its all gone. leave some... because it is food to some of the animals in your pond...