If you want to get into some heavy reading on koi ponds check out
www.akca.org there you will find several articles on pond construction,
pond filtration, water quality, fish health, etc. Click on Koi Health
Advisor in the Menu. ~ jan

See my ponds thru the seasons and/or my filter design:
http://users.owt.com/jjspond/

~Keep 'em Defrosted~
Tri-Cities, WA Zone 7a
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