Posted in Koiphen by me, figured I'd post it here too, fyi.

For the non-chemically inclined.... string algae will decline with
maturity of the pond.

Before the wide use of UV we use to say, 1st year pea soup, 2nd year string
algae, 3rd year balance. Of course stocking level plays a big part on how
bad it gets, or messing with the balance by doing BIG water changes, rather
than small weekly ones, or worst scrubbing the pond of the good fuzz
algae. All of the above, or adding algaecides (this includes PP) slows down
the maturity time.

Now many mature ponds will get string algae during the winter. One year
while teaching a pond class we took the class on a field trip to various
club owners. It had been a very sunny winter and the ponds were clear, but
really thick with S.algae.

My home ponds, and the demonstration pond, I chair at a Master Gardener
demonstration garden, were string algae free. Why, you might ask? Because I
leave leaf screens (screening or shade cloth) on them all winter.

I know a new ponder might not want to do this, I didn't either, but it sure
cut down on winter & early spring maintenance (wind blown debris) and the
worry of winter predatory birds. {I use Scarecrow sprinklers during the
ponding season.}

Regarding feeding pond plants, as long as one uses tabs inserted into
mud-type media, the potassium (what algae prefers) won't leach. Throw Tabs
do not contain potassium and are also safe. Pond plants are the best
natural defense from algae during the season.

For more info read: Green Water by Norm Meck
http://www.vcnet.com/koi_net/GRENH2O.html
~ jan

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See my ponds and filter design:
www.jjspond.us

~Keep 'em Wet!~
Tri-Cities WA Zone 7a
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