Author Options:

Blanket weed killer Answered

My pond gets blanket weed each year. One of the causes is excess nitrogen, but since some of this is due to run-off from farmland, I can only control it to a small extent. I have seen electronic devices sold which are a control box, with some wires which wrap around and around the pipe from the pump/filter - obviously some kind of magnetic or pulsed field is created and this wrecks the blanket weed cells without harming other plants or animals in the water - has anyone any idea how to make one? As you can see from pic2 we get tadpoles, small fish and things - the blanketweed can get so thick that the little fish get trapped in it! I have to pull it out, but often you end up pulling fish etc with it, so I'd like to resolve it. We use barley straw to prevent green algae, but it does not prevent blanketweed.


The Lillies have done it! - this summer the Lilly plants have matured more fully and are now cutting enough sunlight off from the blanketweed that it has not been an issue. By the time the lily leaves brown off (now) for winter, the blanket weed life cycle is also over. I also suspect the lillies are taking up more of the nitrogen as it is an excess of nitrogen that can also cause blanketweed  - good old mother nature saves the day!

"with some wires which wrap around and around the pipe from the pump/filter - obviously some kind of magnetic or pulsed field is created"
I think you'll find magnets or crystals are just as effective as that, but not quite as good as a pyramid with perfect geometry.


..but you get that just-rained fresh smell of ionized water...

Pah, pyramidal water is far superior... it's down to the hydrogen-bond angles y'know. L

How much is a litre of Kaballah water as preferred by Her Madgesty?

I wouldn't know - if there's a connection between pyramids or hydrogen-bonding and Kabbalah -I'd rather not know about it. L

Can you see yourself building a small box "garden" outside of the pond, through which you run the water in a loop? In there you could grow plant material which would utilise the nutrients which the weed is otherwise thriving on? L

The salt marshes around here, have phragmites plants as a "weed" that seems to filter the pollutants before it goes into the bay but it propagates wildly and is tough to contain. Maybe a few catfish or algae eating critters would do.

I was thinking of something like a reed-bed - so that sort of thing. Out of the pond, it could be harvested and composted (or otherwise 'used') L

Can this be controlled with simple aeration? Solar powered sprinker pump or propeller to keep the stagnant water moving? Or will maybe the extra oxygen add to the problem.

A town near to us has a large pond in the centre which had an algae problem. They solved it by floating a savonius windmill on a raft, which mechanically pumps air down into the depths of the pond to aerate it. It seems to have worked.

waterlilies, lots of waterlilies, if you can cover 80% of the surface then the hair algae should be out competed.

As far as I know, the only cure is Algicide eg Blanc-Kit 7.99 for 1500 gallons The only product on the market that kills blanketweed. It works by interfering with blanketweed's bio-processes with terminal effects. Otherwise, you would have to eliminate the food source somehow, the nitrates. Covering it (if practical) also works in killing it off, but then again, that is normally very impractical.