"Tumbleweed" wrote in message
. ..
"Tim Nicholson" wrote in message
...

snipped
water is a particularly turgid green colour...
Last year we tried Algo-rem from Tetra, and whilst we observed a
small improvement over the summer, the pond *really* cleared up during
the winter, but once the sun and any form of heat came back in spring
this year, we're back to the same green murk once again. I also have
some barley straw bundles which I was also told would help, but as yet
(2 months on) they're not looking very efficient.

Draining wont do it it will just reoccur. As already posted there are
several routes to clear(er) water, the one that worked for me was a filter
with a UV light, plus lilies (though it was the UV light that really did
it,
the lilies just help to keep it clearer. IME chemicals to clear the water
dont work well and do harm the plants.

I agree with Tumbleweed - chemicals don't seem to make much difference and I
am wary of their effect on the fish. I can't confirm whether barley straw
bundles work, though I did leave one in the pond last summer (the water
always clears in winter as algae, etc. dies). I also have a shade which
offers some protection from the sun during the summer, reducing algae
growth. If your pond has been badly neglected it might be necessary to drain
it and clear away all the rotting debris, and a vacuum pump might be the
answer, but you should only need to do that once. Nothing beats a good
filter system (left on permanently) and regular maintenance - removing
unwanted leaves, algae, etc.
HTH
Gilbert