Scrubbing a koi pond?

[SoundUser]

Is anyone using a scrubber on a koi pond??? Wondering how big a one sided screen would need to be? powered by the sun.
Pond is about 12 foot x 5 x 4.. im going to work out the vol.

[SantaMonica]

Several people are. Solar powered, as big as you want, really. Only limited by water flow, and how large of a thing you want to clean.