bannrikae wrote:
The makers of the Skippy seem to think that square tanks don't work as
well as the skippy as there are dead spots in the corners, and you
don't get the same swirl/vortex effect.

What media are you using Davidm. Do you clean yours as skipy recommend
never to clean their filter, which sounds good to me!

I'm using the rotary floor scrubbing mats that they describe. There are
a few online cleaning suppliers that sell them. I cut them up into 1"
squares with scissors, it's tough going. Probably best to try and get
hold of an electric tool that can do it faster, perhaps a rotary saw or
reciprocating blade.

Our filter gets cleaned before and after the summer season. It
accumulates about 2" of silt in the bottom. My plumbing is not as
complex as Skippy describes, so the swirl thing is not going on. That
probably limits the final digestion of the waste due to static areas of
sediment.

Also mine cannot be flushed out completely without removing the media.
If the media is bagged or retained by some kind of net it's pretty easy
to remove during the clean. Our previous Oase filter required cleaning
once a week during summer, so the Skippy was a very welcome change.

The basic idea is upflow filtration through heavy matting with aeration.
It's a component step of most large commercial koi filters. However you
choose to interpret the Skippy design, I'm sure you will find it
successful and effective at keeping your pond clean.
DavidM