Can anyone advise on any good sites etc with instructions on
what's needed for the botton drain & some installation and construction
guidelines?

If you check out my website you can find info on bottom drains and how we
did it. Click on *Lily Pond* and you'll see the bottom drain. As far as the
filter it goes to, it is under *My Filter* and *Demo Pond Filter*. There
are bigger bottom drains, you might need 2 for 6,000 (gallons?). ~ 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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