"PlainBill" wrote in message
...
Thanks for the input, especially confirming that the water irises are
a relativly minor part of the 'ecology'.
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In my ponds they're not minor since they grow rapidly and spread like
wildfire using nutrients as they go. Some of our irises reach 5' tall and
are covered in yellow flowers in the spring. All you need do is add Potash
at 1 to 2 Tbs. per 1000 gallons once a month or so. With Potash they're not
limited to how much Nitrates and Phosphates they can take up - they grow
wild. The fish use their overhanging roots to spawn on. Another rampant
grower is Pickerel weed. What I have learned from experience is the more
plants, and the larger they grow - the better!

I find the koi nibble the roots of water lettuce and water hyacinth to the
point they barely grow, limiting their uptake of excess nutrients in the
water.
--
Reel McKoi.... frugal ponding since 1995...
My Pond & Aquarium Pages:
http://bellsouthpwp.net/s/h/shastadaisy
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