"Kay Easton" wrote in message
...
In article ,
Cumberpach
writes
You could always buy a couple of portions of Azolla Filiculoides
(Fairy
moss) from Bromfield and when it covers half the pond, skim it off
onto the
compost heap. I would recommend a UV lamp to assist filtration, but
this
will only get rid of the algea and not the blanket weed.

Be careful with that, though. Azolla is very vigorous and has spread
to
many of our natural ponds where it will grow into a thick
inpenetrable
layer and is very difficult to get rid of.

Despite its common name, it is in fact a fern.

And it really composts very well. Many years ago we were lucky enough
to have a house with a garden abutting a very large pond. Its surface
was well and truly fouled with both Azolla and duckweed, for which I
was truly thankful, as it formed a prolific source of compost
material.

Franz

"Jaques d'Alltrades" wrote in
message ...
The message
from Kay Easton contains these words:
In article ,
Cumberpach
writes

You could always buy a couple of portions of Azolla Filiculoides
(Fairy
moss) from Bromfield and when it covers half the pond, skim it
off onto the
compost heap. I would recommend a UV lamp to assist filtration,
but this
will only get rid of the algea and not the blanket weed.

Be careful with that, though. Azolla is very vigorous and has
spread to
many of our natural ponds where it will grow into a thick
inpenetrable
layer and is very difficult to get rid of.

Despite its common name, it is in fact a fern.

Isn't that the stuff which has cost about nine million (pounds) to
control in two large lakes?

I have a feeling that you might be thinking of water hyacinth.

Franz

The message
from "Franz Heymann" contains these words:

Despite its common name, it is in fact a fern.

Isn't that the stuff which has cost about nine million (pounds) to
control in two large lakes?

I have a feeling that you might be thinking of water hyacinth.

No.

--
Rusty
Open the creaking gate to make a horrid.squeak, then lower the foobar.
http://www.users.zetnet.co.uk/hi-fi/

On Thu, 8 Apr 2004 15:08:27 +0000 (UTC), "Franz Heymann"
wrote:


"Heather" wrote in message
. com...
"Franz Heymann" wrote in message
...
"Heather" wrote in message
om...
I have
topped
up a few times with nasty tap water

What is nasty about your tap water?

Merely that it is tap water! I understand that it increases the
level
of nutrients in the pond and that leads to more weed? It's
perfectly
nice to drink!

That is an old wives' tale. I had 17 tanks of tropical fish at one
time, and they were regularly replenished with tap water, in spite of
the boloney written about using only rain water. Now and again I used
to phone the water company to send me a copy of the latest analysis
summary, just so that I could keep tabs on it. It never had any
excess of plant nutrients in it.
The truth of the matter is that rainwater itself is not all that pure
and is actually often quite seriously acid. About its only virtue is
that is it usually softer than tapwater.


Had also unplugged the magnetic "aqua-mate" device attached to
the
filter inlet before I read about this possibly helping to reduce
weed
in the pond. Have now reconnected this and we'll see if it
helps.

That device is a con trick.

Is this from your own experience? I'm willing to ty it since the
last
people left it so it wasn't me that was conned into buying one!

Firstly, I am a retired physicist and I know of no physical process by
which the weak static magnetic field in such a device can disrupt any
chemicals or biological cells, or can have any softening effect on the
water by physically diverting the carbonate ions. ( The snake oil
sellers frequently sell the same device as a water softener.)

Secondly, one of my colleagues, a civil engineer, was arguably the
most respected water purification expert in the UK. Some years ago I
discussed the question with him. He had done serious controlled
experiments with such a device, always with negative results.

Thirdly, I used the Alnico toroidal magnet from an old loudspeaker in
my fishtank filter pipe. The magnetic field from such a magnet is
about as strong as can be obtained commercially. It had zero effect
on both the water softness and the algal populations in my fish tanks.
Fourthly, I wrote a long and detailed letter to a firm who advertised
such a device. I gave them quantitative physical arguments about the
unlikeliness that their device might be able to perform the tricks
they claimed it would perform. They replied that the points I raised
were interesting, but that their "scientist" would need a little time
to rebuff my criticisms. That was the last I heard from them, despite
three of four letters reminding them that I was still awaiting the
rebuttal.

They are also sold as devices for improving fuel consumption.