Hi Fishy,
So, despite Justin and me both advising you against these things, you`re still interested eh?
How does it work you ask, well, I`ll tell you the theory of what is supposed to happen. The thing itself is a little box of electronics, 10cms by 6cms, that you are advised to screw to a wall or something under cover, and adjacent to your pipework, to stop it from moving about. Out of the bottom of this box come two 210cm long wires that you have to wrap tightly round your filter return pipe, one clockwise and one anticlockwise, which are then secured with plastic zip tie things. OK,
![Wink :wink:](./images/smilies/icon_wink.gif)
, still there? When you turn it on, "an LED will flash on the top of the unit, indicating that the controller has powered up and that the program is sequencing through the range of electronic frequencies". Apparently the range of randomly selected frequencies are then transmitted through the pipe, into the pond water, thus "controlling" the blanketweed. "In the first ten days you should notice the blanketweed ceases to grow, and then over the next three to six weeks to diminish". You are advised to leave it turned on all the time, until the winter, when you are told to turn it off till spring arrives.
Interestingly, having read through all the blurb in the instructions again, NOWHERE do they claim that the devise will KILL blanketweed, only `control` it.
I would say that the reason that you haven`t heard of this make before, is because they realised that the things were absolutely useless, and stopped making them.
I hope this helps in your decision
Chris
PS Have you considered magnets yet, these were also reckoned to kill blanketweed?