What you can do to help with the algae is a 2 inch mat of polyester batting. put a
pump in the bottom of a bucket, put the batting on top and let it drag the water thru
the batting. you need to be able to pull the bucket up, remove the batting and rinse
the green out pretty well. the idea is to REMOVE the algae not just kill it off and
return the nutrients to the pond.

I had the same problem and when I did this last spring it removed most of the algae,
cleared the water but left enough algae to continue to clean up the pond. This year
I am trying water celery in a bucket IN the pond over winter. I had a set back when
the koi got into the bucket to ravage the celery and the roots. I will work on the
design this year. My pond is covered with a plastic "lean to". Water celery is the
most winter hardy of the stuff I have tried. the water cress turned black and died,
but I think I will try rooting the stuff inside and seeing if well rooted stuff will
do better. In the meantime the water celery that is left is sprouting nice green.

So I am thinking about a bucket that will sit in the water but with a tomato cage
lashed to it and plastic wrapped around to keep the air a bit warmer and drop my
water heater into the bucket. a flow of water from a pump enters somewhere.

absolutely no sign of spring for the next 10 days here in the frozen tundra zone 5,
Milwaukee. Ingrid

On Wed, 5 Mar 2008 22:11:41 CST, Gareee© wrote:
The problem with veggie filters, is we can still get snow until mid april,
and by then the algae is already in full swing. (the pond is actually
totally green now, even though we're still getting snow at night, and below
freezing temps.)