How best to fix it

Howdy, experienced ponders, from Fort Worth. Here's my 220 gallon pond
last year, sans fish: http://artships.com/fountain.jpg

Powered by a Little Giant PCL-025 475GPH pump,
http://www.littlegiant.com/littlegia...dLegNum/567636 ,
in the filter box, FMS-20,
http://www.littlegiant.com/littlegia...256b25006d28e9

It was Just Fine when it was all just for looks and little sound. Since
the comets, though... Not so much. Now I want more water going over the
falls, and none of that pea soup, either. And generally clearer water,
without what looks like suspended dust.

According to Little Giant's website, I should be able to connect the
existing pump to a better filter, the PF300,
http://www.pondfiltration.com/pf300.html (it looks to be a Little Giant).
I know I can bump-up the waterfall volume a touch by replacing the hose
with a slightly larger diameter.

My main question is, will the pf300 filter with the 475GPH pump clear-up
the water? Or, should I build a skippy filter into the lowest of the
brownish plant beds? If so, how much more pump will I need to drive it?
1000gph (I'm guessing because 475GPH just doesn't seem like very much)?
Feel free to chime in with, "The best filter is..." and ditto with a pump.

Possibilites abound, paralyzing selection. But you've all been there.

John
*wave* to Gail F.