IMO, a pump that size ought to be in an-out-of-the-pond filter, otherwise I
think your best bet of the styles of in-pond-pre-filters is to make yours
bigger. I believe K30 uses a laundry basket with lava rock, Or use the
largest mesh baskets zip tied together, like www.aqua-mart.com carries.
~ jan

See my ponds and filter design:
http://users.owt.com/jjspond/

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