Hmm a filter, I played around with that idea, it needs an extremely fine medium such as sand or ideally DE powder (0.5 micron filter rate), I have both and I tried with the sand but found I needed a sealed filter cannister to be pressure fed by the pump, gravity couldn't push the water through quick enough. Tried also with standard filter mediums but the suspended sediment was too fine so was fairly ineffective. In the end I figured for a one off it was going to be too much effort or I was going to end up with a floor full of skanky water
